All right, welcome back everybody to our second lecture on Revelation and Daniel. We are continuing our study there in chapter 11. We had just mentioned or we were talking about the two witnesses that God would send. Just some thoughts on how would these two witnesses appear on the earth? How would they be raised up in the middle of the tribulation? And I'm just sharing a few possibilities of how this would happen. Let's pick up now from verse 7 and let's please read till verse 14. Revelation chapter 11 verses 7 to 14. Could somebody please read that passage for us? Maybe Prince or the Prince. If you can read Revelation 11, 7 to 14, please. Yes, when they finish their testimony, at the best that assigned out of the bottomless pit will make way against them, overcome them and kill them. And their hate bodies will lie in the state of the great city which spiritually is called Sodom and Egypt where also our Lord was crucified. Then those from the people, tribes, trunks and nations will see their dead bodies three and a half days and not allow their dead bodies to be put into the grave. And those who dwell in the earth will rejoice over them. MacMerry and Saint keep to one another because these two prophets tormented those who dwelt on the earth. Now, after the three and a half days, the best of life from God entered them and they stood on their feet and great fear fell on them who saw them. And they heard a loud voice from heaven saying to them, come up here. And they ascended to heaven in a cloud and their enemies saw them. In the same hour, there was a great earthquake and a tenth of the city fall into the earthquake. Seven thousand people were killed and the rest were upright and kept glory to the Lord of Heaven. The second woe is burst. The second woe is burst. Behold, the third woe is coming quickly. Thank you. So this passage is telling us what will happen with these two witnesses. So like we said, this is going from the middle of the tribulation to the end of the tribulation. So these two witnesses are bearing testimony to Christ. They're preaching. They're proclaiming. They're doing mighty signs and wonders. And of course, people all over the world are seeing and hearing what they have to say, which is very possible today, right? Given all the technology and the connectivity that we have globally, what's happening in one place can be seen anywhere and everywhere all over the world. And so people's nations, all nations are seeing, hearing what these two witnesses are doing. Now towards the end of this tribulation period, the ministry of these two witnesses is going on throughout the second half of the tribulation. Towards the end, this is verse seven, the beast. It's talking about the beast. This term is introduced here. The beast to ascend from the bottomless pit. Now this term will be used again in the 13th chapter. When we talk about the Antichrist, right? So this beast here, we could say at this point, is referring to the Antichrist. Now he comes to the bottomless pit because he's literally, he's empowered by the forces of doctors. You will see that. So the Antichrist kills these two prophets of God. And their bodies are lying in the street of the city of Jerusalem. Right? So now here in verse eight, the city of Jerusalem is referred to as Sodom and Egypt spiritually. So it's telling us that at that time, you know, the spiritual condition of the city of Jerusalem is going to be so corrupt. Meaning it's gone. It's like Sodom and it's like Egypt. Egypt known for its idolatry or worship of false gods. Sodom known for its immorality. And so Jerusalem has become like that spiritually. But anyway, these two false prophets, their bodies, they're killed by the Antichrist. Their bodies are lying in the city of Jerusalem. And it says that for three and a half days, this is verse nine of Revelation 11. And the whole world is watching this. You know, we, we can use this as an indicator of how close we are towards the fulfillment of this, of Bible prophecy. Because if we went back in time, say 30 years ago, for the whole world to watch, to see something 30, 40 years ago, for the whole world to watch something would not be possible. You know, yeah, it would come in the newspaper or something, one or two days later. But they can't, they can't see it in real time. Right. But it was nine is saying, people from tribes, tongues, nations will see their bodies. Right. So today we are living in a time when this is possible. When you can see, you know, people can see on their mobile devices in real time, you know, live streaming, they can see videos. They can see live reporting, you know, from the city of Jerusalem. They can see directly on their mobile phone. They can see the dead bodies of these two people. Right. So about 40 years ago, not possible. Here we are in a day and a time when Revelation 11 verse nine can actually be fulfilled and people can all over the world can see, you know, what's happening. So this says here that people's tribes, tongues and nations will see their dead bodies three and a half days. It means the bodies will be lying there in Jerusalem for three and a half days. And then something powerful will happen. It says at the end of the three and a half days, the bodies will come alive and God will raise them up. And while everybody is watching, their bodies are sent into the sky, into the clouds. It says the enemy saw them. Now, is this possible? Of course.  Elijah was caught up into heaven. The Lord Jesus was caught up into heaven. All these are physical movements. And so for these two witnesses to be resurrected and taken up into heaven. Absolutely not a problem. Right.  Everyone taken up into heaven. So for these two witnesses, for their bodies to be resurrected and taken up into heaven, God can do it. Right. So when that happens, it says, where's the teen is a great earthquake. A tenth of the city of Jerusalem is destroyed. And about 7000 people's lives, people are killed. And this causes many people to fear and, you know, recognize that in hate, all this is this is God. The God is doing something. Right. And so the angel announces here. Okay. Two woes have passed. There's one more coming.  So we've had the seven or the first set of seven. Sealed judgments, first wall, second wall, which is the first set of the second set of judgments. There's seven trumpet judgments. And then the last set, which is the bowl judgment. So this angel is announcing the third wall, third set of judgments is coming. And at that time, while the angel is announcing that there's going to be this third war or this third set of judgments. So during the seven year tribulation, there are three sets of seven judgments each referred to as a first, second and third wall. I mean, it's declaring judgment. So when this angel announces that there's going to be this third wall, this third set of judgments at that time, revelation 1115, the seventh angel is sounding. So this is the conclusion of the second wall or the second set of seven judgments. So when the seventh angel sounds, like I mentioned in the previous lecture, there is a proclamation, there's an announcement that the kingdoms of the earth become the kingdoms of our Lord. So it doesn't mean it's happening at that instant. It's an announcement. It's going to happen. And like we said shortly after that, you know, the Lord Jesus comes and he conquers all the nations, right? So it's an announcement that that is going to happen. So let's read Revelation 11 verses 15 to 19, please. Somebody could read that Revelation 11 15 to 19. Anybody whose mic is okay? Conan, if your mic is okay. I will read. Can you hear me right? Good, I can. Then the seventh angel sounded and there were loud voices in heaven saying the kingdom of this world have become the kingdom, kingdoms of our Lord and of his Christ. And he shall reign forever and ever.   The nations were angry and your wrath has come.  Then the temple of God was opened in heaven and the ark of his covenant was seen in his temple and there were lightnings, noises, thunderings and earthquake and great hail. Thank you. So the seventh angel sounded. So that's the last of the trumpet judgments. Now in this, you know, when the seventh seal was opened, there was silence in heaven. I think, you know, there was no activity. Similarly, seventh trumpet is sounded. There is there's no judgment on earth year per se, but there's an announcement. There's a proclamation. There's great celebration. The kingdoms of this earth of this world have become the kingdoms of our Lord and his Christ. So there's this proclamation. It's going to happen. And all the kingdoms of the earth will be taken over by the Lord Jesus Christ. Now what we said that will be fulfilled at the end of the battle of Armageddon Revolution 19. But now it's an announcement. It's going to happen.  You know, many of the servants of the pro many of the prophets were killed and saints were martyred. God is going to reward them. God is going to, you know, in some way, what I want to say is like he will take vengeance upon the nations for the way the prophets and the saints were treated. So they're just saying, God, you have redeemed us. You have brought us in and you or God will judge the nations and you will reward your prophets. And they're announcing that you will destroy.  And John sees the temple of God. He sees the Ark of God in heaven. Right. So that's the real temple, the Ark of God, the presence of God. So Revelation chapter 11, Revelation 11 verses one to 14. The first part of the relation is taking us through the three and a half year period with respect to the two witnesses. And then we come back to the time in the middle of the tribulation where the seventh trumpet has sounded making the announcement that this is what's going to happen. Now, Revelation 12 is similar to Revelation 11, meaning is giving us some insight what's happening from the middle of the tribulation till the end. But this is with respect to what the devil is going to be doing. What is Satan going to be doing during the three and a half year period? Right. What's he going to do? He is going to be in panic mode. He is going to know that his time is short. He's got very little time left. That is three and a half years, literally. And he is going to do, I mean, he's going to, you know, it's like he's operating desperately. So one of the things he does is, as we will see, I'm just giving a little preview of chapter 12 and then we will read it. One of the things he does, Satan, he tries to penetrate heaven, his final attempt. He tries to break through into heaven, but he can't. He tries to, you know, I'm so angry, like, let me get my hands on God. No, no way. There's Michael and the Archangels. They keep Satan and his demons out of heaven and push them off to the earth. He comes back to the earth, knowing his time is short, three and a half years left. And what he does is he goes after Israel, the nation of Israel. Now, why is he angry with Israel? Because it was through these people that Jesus Christ came into the earth. So it's in one way Satan is trying to take out his anger against these people for ushering Christ into the earth. So for the next three and a half years, that means from the middle of the tribulation to the end, he knows his time is short and he's going to go with great vengeance against Israel. But more specifically, we will see in Revelation 12, against those who believe in Jesus Christ. Those who have the testimony of Jesus Christ and have the word of God, he's going to go very intensely against such people the last three and a half years. That's what he's going to do. Okay, so that's what chapter 12 is about. But to convey that to us, chapter 12 uses a lot of figurative language or what people call us, prophetic imagery, a lot of images. Now these images are not difficult to interpret. It may look difficult at the very beginning. I mean, if you read it initially, but actually it's not difficult. So let's go ahead and I think we've referenced this chapter on many different occasions. So it should be fairly familiar to us. Let's go Revelation 12. We will read verses one through six, please. Somebody could read that. Revelation 12, one through six. Maybe Kiran, if you want. Can you read that for us, please? Yes, sir. Now a great sign appeared in heaven, a woman clothed with the sun, with the moon under her feet. And on her head, a garland of twelve stars. When being with child, she cried out in labor and in pain to give birth. And another sign appeared in heaven. Behold our great fairy, red dragon having seven heads and ten horns and seven deities. Diadems. Diadems on his head. His tail drew a third of the stars of heaven and drew them to the earth. And the dragon stood before the woman who was ready to give birth to Devar, Devar her child as soon as it was born.   Then the woman played into the wilderness where she has a place prepared by God that they should feed their 1,260 days. Thank you. All right. So let's try to understand this. I just want to point out the end of verse 6, 1,260 days. We're seeing this again, right? It's 42 months approximately or three and a half years. So once again, the timing of Revelation 12, and it's going to be repeated again later on in this chapter, is the middle of the tribulation. So he's talking about something that's going to happen in the middle of the tribulation and then continue. But he's giving us the background. He's giving us the main players or actors who are going to be involved. First of all, starting from verse 1, he talks about a woman clothed with the sun, the moon, and 12 stars. So when we read that, you know, a woman, sun, the moon, 12 stars, that looks like a strange picture. But when we look in the Bible in Genesis 37 and verse 9, so if you turn with me there, Genesis 37 and verse 9, you find that when Joseph had his dream, God used similar, Genesis 37 and verse 9, God used similar picture. You know, he said, Joseph said, I have a dream. I've dreamed a dream. The sun, the moon, and the 11 stars bowed toward me.  Genesis 37, 9 and 10. So it seems it's very clear here that the same image, sun, moon, 11 stars, the woman with the sun, the moon, the 12 stars, in this case, represents the nation of Israel. Because God used that imagery. And the son was speaking to Joseph, who was one of the 12 stars, the 12 sons. He's using that to speak to him about the nation of Israel. So we can clearly see this woman here represents the nation of Israel. The other indicator is from this woman came a male child. And who is this male child? It tells us here in verses four and five that this male child was going to rule the nations with a rod of iron. And that same terminology is used in Revelation 19 and verse 15. So between Revelation 19 and verse 15, it's used about Jesus. Revelation 19, 15. I was talking about Jesus that out of his mouth goes a sharp sword with it. He will strike the nations and he himself will rule them with a rod of iron. So we can, we know, we immediately reference this to the Lord Jesus Christ. And we also see, I think it's in Isaiah 11. Let me just turn there, Isaiah 11. And verse four, Isaiah 11. And verse four, it's clearly talking about Jesus who's the anointed one. And there once again, it says he will strike them with the rod of his mouth. Isaiah 11 was for talking about Jesus.  So who's the woman, the nation of Israel? She's the one who gave birth to this male child that is the Lord Jesus Christ. The one who's going to rule the nations with the rod of iron and the one who was caught up to God. And then we see a red dragon. That's in verse three, a great, fiery red dragon. Now, what does he say about this red dragon? Seven heads, ten horns. Seven diadems on his heads. So the number seven, as we said in the very beginning represents, seven represents perfection. So saying that this dragon, Satan, is, you know, perfect in his headship and ten horns, horns representing power, authority, leadership.  So that's this red dragon. Now, who is this red dragon? We will read on and we will see in verse nine that this great dragon, it says in verse 12 verse nine, this great dragon, the serpent of all the devil and Satan. So this red dragon is interpreted for us clearly there in Revelation 12 9 as the devil, Satan. So the red dragon represents the devil, Satan. The woman was a garland of sun, moon and 12 stars. She is the nation of Israel. The male child is Jesus Christ. We understand that very clearly. And another side note we can see in verse four that this dragon drew a third of the stars of heaven, Revelation 12 verse four, drew one third, one third of the stars of heaven. So the stars of heaven here are imagery or image of the angels of God. So when Satan fell or when Satan rebelled against God, he took with him one third of the angels. So this is where Revelation 12 verse four is the scripture from which we are. We say that Satan in his rebellion took one third of the angels of God with him at that time in his rebellion. And of course they were cast out of heaven at the time. So what is the dragon doing here in verse four? It says here, the dragon stood by the woman to devour her child. So that means Satan made a first attempt to devour Jesus, to destroy Jesus Christ. And we know, and if you look at history, we know that at the time of Jesus birth, Satan attempted to do it. How did he do it? How did he attempt to do it through the decree of King Herod? King Herod said, you know, go and destroy all the children two years and below in the region of Judea. So you can see how the dragon worked through somebody in leadership. In this case it was King Herod in an attempt to destroy the male child, which is Jesus Christ, as soon as he was born. So that's Revelation 12 verse four. So these are talking about events in the past. Things that have happened in the past. Satan drew one third of the stars of heaven. That is one third of the angels.  So this was there. But now we're coming back into what's going to happen during the tribulation. What's that going to happen? Verse six, the woman fled into the wilderness. She had a place prepared by God to feed her and keep her for 1000 to 60 days. That means this is a picture that God will protect the woman, which is the nation of Israel during that three and a half year period. Now the second half of the tribulation is often referred to as the time of Jacob's trouble. You will see that in I think it's Jeremiah chapter 30. Let me just look it up. Jeremiah 30 and verse seven. Yeah, Jeremiah 30 verse seven. It is often referred to as the time of Jacob's trouble. So this is the second half of the tribulation is a time when Israel is going to face its worst time ever. You remember in Daniel chapter 12 when we read it. The angel Gabriel told Daniel that and I'll give you the exact words in Daniel 12. The angel Gabriel said, this is in worse, worse one. There shall be a time of trouble such as never was since there was a nation, even to that time. And at that time, your people shall be delivered Daniel 12 verse one. In other words, the angel Gabriel told Daniel, you know, there's going to be trouble. It like never before. And especially the reference to your people, but your people will be delivered Daniel 12 verse one. So that's what's happening here. Israel is going to see such great trouble, but God will preserve them. So when Revelation 12 verse six says that God prepared a place for Israel in the wilderness. It's a picture of God somehow protecting this people. Now, is it a literal wilderness that, you know, the Jewish people are going to escape into and hide? Or is it just a figurative language that God is going to protect the nation? But I think it's more of a figurative language that, you know, that just saying that God will protect them. But there are some who try to, you know, try to figure out where could this wilderness be? Where the Jewish people could go and hide themselves. And so some people, you know, you might read this in commentaries. Some people would say, well, the wilderness is towards the East into Jordan. There's a lot of land that's like wilderness. And it's likely that the Jewish people go and, you know, stay there in safety. Some even may think, well, maybe they go down into Egypt because in the past, God has used, you know, Egypt down south of Israel as a place of safety. You know, but if you look literally these days, there really is no place of safety because, you know, if people want to attack, they can attack anywhere given the kinds of weapons that are available, missiles and aircrafts and all that. If you want to attack a people, you can attack them anywhere. So they're really physically a place of safety. It's not so easy unless they go underground, which is possible. Or we could just say, look, it's just telling us that God will provide a place of safety for his people. Right. So I'm just giving you, you know, how different people look at verse six. And it's repeated again later in this chapter. So let's pick up now from verse seven, Revelation 12 verse seven. And let us read till verse 12, please. Somebody could read Revelation chapter 12 verses seven to 12 for us. And war broke out in heaven. Michael and his angels fought with the dragon and the dragon and his angels fought. But they did not prevail. Nor was a place found for them in heaven any longer. So the great dragon was cast out. The serpent of old called the devil and Satan was this who deceived the whole world. He was cast to the earth and his angels were cast out of him. Then I heard a loud voice saying in heaven. Now salvation and strength and the kingdom of our God and the power of his Christ have come. For the accuser of our brethren who accused him before our God day and night has been cast out.  And they did not love their lives with the death. Therefore rejoice, O heavens, and you who dwell in them. Woe to the inhabitants of the earth and the sea, for the devil has come down to you. Having great trust because he knows that he had a sort of time. Thank you. So these verses, verses 7 to 12 are describing a scene of heavenly warfare, spiritual warfare, a war in the heavens. It's saying this dragon Satan, he makes an attempt to penetrate into heaven with all of his angels. But then Michael and the heavenly angels just say no entry. They don't let the dragon Satan and his demons even get into heaven. And so they're sent back to the earth, they cast out to the earth. Now, and then there's this great proclamation in declaring the greatness of our Lord in Christ. And the accuser of the brethren, accuser of the brethren, he's cast down. And it tells us that people, the brethren, the people of God, they overcome the adversary, the enemy by the blood of the Lamb, by the word of the testimony. And then it says, you know, verse 12, the devil has come with great fraud because he knows he has a short time. Now, there are a lot of questions here with this passage, especially whether this is describing something that's going to happen in the tribulation, or is it describing something that has happened in time past. And so here again, you have two different, you'll have at least two different, different viewpoints. There are some who say, who say, Revelation 12, 7 through 12 is describing something that has happened in the past. But for me, my position is, or my understanding is it's writing about something that's going to happen in the future at that time, during the tribulation. Why do you say that? Well, the reason I say it is because verse 12 does say, let's say it has come with great fraud, knowing that his time is short. And then it specifically says that, yeah, knowing that he has a very short time. So it's saying that. So meaning is pointing to something where the devil's been accustomed to the knowing that the time is very short. And because of that, I feel that this is something that's going to happen, not somewhere that has happened. And when it does say verse 11, they overcame him by the blood of the lamb. It's talking about how we overcome the devil, even now by the blood of the lamb, but more so the tribulation saints, the brethren who are there in the tribulation, for them also, they overcome the devil by the blood of the lamb. So we do so now, but this is also applicable to them during the tribulation. The other thing that that's a point of point to make note there is that the devil is called the accuser of our brethren who accused them before God Day and Night has been cast out. So Satan is the accuser of our brother or the brethren, the people of God, that's his job. He accuses them. Now, how do we understand this? Does this mean that the devil goes into heaven before the throne of God and accuses us, you know, personally before the throne of God? Should we understand it like that? Or should we understand it as he's accusing us to us before our God, bringing condemnation, guilt and shame to each of us before our God? So again, here again, there are two different views, and then there are some who've built, you know, a lot of ideas around Satan accusing each one of us before the throne of God. And therefore, we have to go before the throne to defend ourselves, which I don't subscribe to because we have an advocate with the Father Jesus Christ. And when Jesus died on the cross, John 13, John 16 verse 8 says that Satan was condemned the ruler of this world, the God of this world. He was condemned. That means the verdict was announced 2000 years ago that Satan is condemned. We are acquitted. That's already done. So there's no more court case proceedings. It was all over on the cross. So there's no more devil going before God to accuse us because the judgment of the verdict was passed on the cross already 2000 years ago. And therefore the New Testament calls us as acquitted people. That means we are righteous. We are not being condemned before God. We are acquitted by God. We are justified by God. So there is no more court cases against us happening in heaven. So therefore, when the scripture says here that Satan is the accuser of the brethren, I like to understand it. The way I understand it is Satan accuses me directly, me before my God. So he tells me, I says you are unworthy.  You're no good. God is upset. God is angry with you. So he's accusing me in my mind before my God. So that's the accusation of the enemy. It's not like he's going to heaven before God accusing me. That cannot happen because the court case was already dealt with. So he's accusing me directly before my God. He's the one who accused me before my God. So that's the way I understand it. So I don't subscribe to... There's a lot of teaching that's been going on. Talking about the courts of heaven and people having to go, believers having to go to heaven, come before God and defend themselves from the accusations of the enemy and all of that. I think all of that is made up. It's not real. It's unnecessary because the court case was already dealt with on the cross. You and I are acquitted. You and I are... There's no condemnation against us. You and I are already justified. We already have peace with God. The accusations we face is what the enemy brings to us in our mind today. And we have to use the word of God against those accusations. And we declare what the blood of Jesus Christ has already done for us. That's how we overcome the enemy. So that's another thought here from this passage about the accuser of the brethren. That's the work of the devil bringing accusations and condemnations. So what we see here, and so Revelation 12, 7 through 12, is in the middle of the tribulation, Satan is going to make one final attempt to penetrate heaven. He's not going to be able to do it. The angels of God, Michael and the archangels, Michael, the archangel and the other angels will prevent him, push him back. And his only option now is whatever he could do on the earth and he will come with great wrath because he knows his time is short, meaning he just has three and a half years left. Okay, let's read the remaining verses of Revelation 12 and we'll try to finish that before this class is over. Revelation 12 verses 13 to 17, just four verses. Somebody could read that for us. Revelation 12, 13 to 17. Now when the dragon saw that he had been cursed to the earth, he persecuted the woman who gave birth to the male child. But the woman was given two wings of a great angel that he might fly into the wilderness to her place where she is nourished for a time and times and half a time.  After the woman that he might cause her to be carried away by the flood. But the earth held the woman and the earth opened its mouth and swallowed up the flood which the dragon had softened out of his mouth. And the dragon was engaged with the woman and he went to make war with the rest of her offering who gave the command, helped the testimony of Jesus Christ. Thank you. So verse 13, now when the dragon saw he had been cursed to the earth, what did he do? He went after the woman. Who is the woman? Israel as a nation. So he's going to persecute. He's going to go after the woman. And verse 14 says, but this woman had given wings like a great eagle. So she could escape to a place in the wilderness where she's preserved for time, times and half a time. From the presence of the serpent, time, one times to half a time. So one plus two plus half, three and a half years. So once again we can clearly say that Revelation 12 is talking about the middle of the tribulation till the end of the tribulation because it's referencing once again that three and a half year period. So for three and a half year period, Satan is going to go attack Israel. He's going to persecute. He's going to try to do all he can against the nation of Israel. But God is going to provide a way of escape to the people. Now verse 14 talks about this woman having wings of a great eagle and he goes into the place of wilderness where she is preserved and nourished. So once again, like I said earlier, this could be a literal place maybe in the wilderness. We don't know where exactly. You know, people have tried to propose certain areas where Jewish people could escape in the wilderness. Or this could be something very figurative, like wings of an eagle that God gives these people a supernatural ability to escape from all the persecution that Satan brings. Now sometimes you might find people talking about the wings of an eagle representing America. Now I don't subscribe to it. I'm just saying if you do find it, you can think about it. I say, okay, America would be that nation that comes and protects Israel.  But I don't think that's what it's referring to. I think it's just figurative prophetic language. That's verse 14 talking about God giving the people a supernatural way of escape from the attacks and the persecutions that the enemy brings. Now how exactly is Satan going to bring this persecution? That's described for us in verses 15 and 16.  Now what has it been spewing water? We don't know for sure, but if we use prophetic language to interpret it, water like a flood. If you look at Revelation 17, the 17th chapter, verse 1 and verse 15. Revelation 17, verse 1, it talks about the great harlot sitting upon the great sea, the water. And then verse 15 talks about water representing people's nations, tribes and languages. That means it's not the nations of the world. So if we use that prophetic language or picture here, when it talks about Satan spewing water like a flood, the flood is representing people's nations who are motivated or moved to come against Israel by the enemy. And this is very, very, I feel a very correct understanding because later on in chapter 16, we will see that demons are released on the earth to go and instigate people to come together for the battle of Armageddon. So there again, demonic powers are causing nations to come together for a final battle. So based on these two corroborating references within the book of Revelation itself, we can say that what we're reading here in Revelation 12, 15 and 16 about this big flood is basically people who are motivated to come and attack Israel, persecute them, try to destroy them. But God is supernaturally protecting them, preserving them, nourishing them. And so that makes Satan even more angry. And verse 17 says, he goes out to make war with the rest of her offering. Those who keep the commandments of God and the testimonies, meaning he's going against believers, against the brethren, all out against those who believe in the Lord Jesus Christ. Satan is going out to them. So this is all happening in the second half of the tribulation for that three and a half year period. Okay, so this brings us to the end of chapter 12. Any questions? Is everybody with me so far? Any doubts? Any questions? You've been following? Is it clear? So this Aaron's question, are we going to experience all this? Remember, the church has been taken out of the way, right? So you and I will not be around because Revelation chapter four and five, the church has been raptured. So we are not here. Revelation six verse one begins the seven year tribulation. So we will not be around. But all these things are going to be fulfilled on the earth for the people who are there at that time. Okay Aaron, you got it Aaron? Okay. All right, let's close. I know our time is up. We're going to need to take a break and then get ready for our next class. Can somebody just pray with us? Maybe Dave, why don't you pray? Then we'll dismiss, please. Thank you once again Lord Jesus. Thank you Lord for this class. Thank you. I've been learning so much from your words. All these things that we are learning Lord, I would say that I have been trying to understand them. So that we can know good things and know so that we can be ready and prepared for the future time. Thank you once again. Amen. Amen. Thank you everyone. Please take a break and then we will see you in the next class. God bless by now.


Hello everyone, welcome back to another AI video. In this one, I'm in illusion diffusion. This is a new AI tool. It's built, you can use it on hugging face for free. And it allows you to create stunning high quality illusion artwork or optical illusions. Now let me show you what I've got here. And of course, I will put a link to this in the description below. But here is the first example and the second example even better. But the first one here is I've got my prompt right here. Again, I'm on hugging face. And it says a beautiful cyberpunk town with neon lights, tall buildings, rain and glowing puddles. All right, normally it would create a nice cool image for us. Of course, but look at this or AI art, but look at this, I asked it to use this here as the input illusion. And it sort of chirped out this cool looking optical illusion that's inside the final image. Now I've got the illusion strength at point eight. But I want you to know that a you can increase or decrease the size of the illusion strength. And you can also use your own images. Let me go to the next one here, show you what I'm talking about here. Here we are in illusion diffusion. I used this image of Twitter. You'll notice here that I changed the illusion strength to 1.6 instead of the default point eight. So I doubled the strength that goes way, way up if you want to go. And here we go, look at this awesome image that it created here on the right side, you can see the basically kind of like the little Tweety bird or whatever you want to call the Twitter bird is burnt into it. And look at that. And here we go. And all I put in for a prompt was forest trees, wild animals, a super simple prompt. It gave me this awesome optical illusion. I believe this is called Paradoia. I don't want to pronounce that wrong, but I have another image on how to do this in mid journey. So if you want to see another example, I'll run one for you just to show you what it takes. Again, links in the description below. All you need to do is drop your own image right here. Or you can just select one of the different examples. For example, if you want a nice cool checkerboard, I'll select on this cool checkerboard. And then I'll put in something like, I don't know, Roman villa with, I don't know, tall towers, whatever, something silly like that. I'm going to go ahead. I'm going to change the illusion strength up to let's go something really, really high. Let's go to like two. But well, actually, how high does it go? It goes to five. Let's go with like a four. You want to go, you want to go big? Let's go big. Let's spoil. Let's pour all the spicy Thai sauce in. All right, cool. We're going to go with 4.01. I'm going to go ahead and I'm going to keep that prompt there. And then all you got to do to make this work is click on run. When you do that, you'll see here that there might be a queue. We're in seven of seven. So just keep that in mind. Also, this will not work if you're not logged in. So if you're just using it as a spectator and you're not logged in, I was having a lot of problems using this earlier. So keep that in mind.


After World War II, a team of young Australian migration officers was sent to Europe to interview post-war refugees to gauge their suitability as migrants to Australia. These men were called on to make very difficult decisions, as Harold describes. Well, I've never forgotten a Polish couple. The children had gone a year before to Australia, had settled in well, but they were on a landing permit arrangement to be reunited with their son and his family in Australia, but it was established that the father had tuberculosis, that it was active, and the conclusion was that his lifespan was limited. I interviewed them and I said, well, you can't go. They said, well, why can't we go? And then I said, perhaps mother might be allowed to go. And I contacted Mr. Greenhouse in Cologne and he agreed after consultation with Australia that the mother could go, but the father couldn't go. So I re-interviewed, I interviewed the father, told him what the situation was, I interviewed the mother and told her the situation, then I interviewed them again together and I said, well, now you have to decide as a mother does have a future if she goes, but father, you know your situation.  And here am I, 27, playing God, deciding for this lovely couple. I've never forgotten them. And I said, well, mother ought to go to give her a chance. And she went and for a number of years later, I received cards from that family, from her and from her children. And then the father died within six months of that interview. Also while in post-war Europe, Harold was asked to star in a government film about the refugee selection process, a film called Mike and Stephanie that raised a few eyebrows at the time and for many years after. There were problems in Australia, a feeling that we were too loose in our screening arrangements, allowing undesirables in newspapers like the bulletin were costing in their criticism of call. So a decision was taken, they'd make a documentary on our screening processes just to demonstrate how effective we were and the problems that we were encountering, but what we were doing. So a documentary maker, Ronald Maslin-Williams, with a photographer, Reg Pierce, they were given, allocated the sum of $5,000 and they were told to go and make a documentary. I was notified, and how it came about was that they worked out with the assistance of IRL, a Ukrainian family that had been separated by the war, then reunited and they decided they'd like to go to Australia. And Greenhouse said to me, you're going to be the migration officer. Now it's going to be a proper interview. You may or may not accept the family. And we went to Leipheim, which was a small, there was a children's village there and the screening and the filming took place there in relation to the interview. They were an extremely nice family. I went through the process, if you've ever been in trouble with the police, members of a political party, why are you going to Australia, why have you taken so long to make up your mind about Australia? I was quite happy with the family and what made me more than happy was because I dealt with similar cases. I'd been working for 10 months interviewing by then and I knew the pattern and I knew that IRA would have been quite stringent in their own pre-selection measures to make sure that the family that would be presented would be okay. It was two odd years before the film itself actually was released. They went to Australia, I think, around March 1950 and the film was not released until 1952. It was shown to a group of parliamentarians. They objected to it, they objected to the severity of the interview. I came in, I understand for a lot of criticism that I was too severe, that I was unfeeling in my attitude. The family was tense, they were worried, am I going to be accepted or not. But I was also tense. I was on film and I think I was more worried, if I might say so, than they were. The consequences in Australia was it was never released commercially and also time had passed. We wanted to introduce the Assisted German Passage Scheme and it was introduced. We had a Assisted German Passage Scheme agreement in August 1952, I think if I recall correctly, concluded and so they felt they didn't want any of this to rebound and hinder.


My name is Andrew Metter. I am currently unemployed and I'm loving it. I just got out of the military. I was in Green Beret for a few years. I took the Art of Charm program because it was an itch that I wanted to scratch for a while. It was something that I had been thinking of and felt like procrastinating was hurting my chances at actually living a fulfilling life. People often felt that I was being either harsh or cold or I had this more intense stare. I thought I was angry, but actually I was just thinking and I didn't realize the signals that I was putting off to other people were putting them off. I was super skeptical at first. I didn't know what to expect. I didn't actually personally know anybody who had gone through. I wasn't referred. I was kind of on my own and then I met the other guys from the camp and the next day we got started and I was immediately put at ease. The approach of the instructors was professional, friendly, familiar. They were not judging anybody. They had obviously seen a lot of different personalities come through the place and I think they were relieved that we were pretty male actually as a group. The program is probably for most people the time when you'll have the most social support from other men and for that matter women who work with AOC then you may ever have or have ever had. So if you're in college and you've got a circle of guy friends but they're always judging you or if you're in a workplace environment and you don't feel comfortable talking about certain things with other people going to the boot camp is a useful way to get that out in the open. People aren't going to judge you for anything. You can talk about pretty much anything that you want to. The best moments were seeing the other guys around me change incrementally because it proved to me that I was actually doing the same thing. When I could see it in them, when I could see the enthusiasm peak and guys start to break out of their shell I knew that they were moving in a positive direction because I was working just as hard as they were and putting myself out there as much as they were I knew I was actually improving too. It's no coincidence I'm sure that within two months of finishing the program I'd actually fulfilled a true goal of mine which was to be able to have a longer term relationship and instead of just seeking hookups and being part of the hookup culture or never really leading a fulfilling relationship life. I'd say anybody from college kids, married guys, military, non-military, average working Joes, corporate types everybody comes in and is on the same level so you all work through things together and it's a unique experience like that it's also something I think every man could benefit from especially moving forward, 2015 is coming up and heck man, the world's changing you need to be a charming person you need to be out there networking, getting to know people you need to be positive it's no longer okay just to be harsh and insensitive and still get away with it


Assalamu alaikum dear students, today we are going to discuss lecture number 5 of the database management system course. As usual in the beginning, we will briefly review the topics that we covered in the previous lecture. In the previous lecture, we completed the discussion on the three-level architecture of the database. Then we discussed an outcome of the three-level architecture that was data independence. We also studied two different types of data independence which are logical data independence and physical data independence. After that, we discussed different functions of the DBMS. And at the end of the previous lecture, we discussed different environments of the DBMS, the environments in which DBMS is used. Today we are going to discuss the database application design approach or the design process. So let's start with today's lecture. The first topic that we are going to discuss is the database application development process. Dear students, let me explain a little bit about the database application development process. We can briefly talk about the database development process as well. The second topic is that the process or approach that I am going to talk about here in this course, this is not the only approach. This is not the only process. You will see that in the different books of the database, this process is not discussed in detail. The reason for this is that the main emphasis of the database course is to guide you on the tools and the methodologies that are directly related to design. And the different activities of the database are discussed. The books of the database do not discuss the development process of the database, the application development process. Because it is a very different topic and it has a different subject for it, which is software nearing. And software nearing is one or two or three subjects. It is included in the normal curriculum of BCS and MCS. But what I am telling you here in the process is also a valid and correct process. But the better processes are read in the course of software nearing, in the books. The processes that you read in the software nearing of the methodologies, the part that is related to the database development is read here. The emphasis of this course, the database course, is associated with the part of the system development where the database development is concerned. But for the completeness of this course, I will discuss the traditional approach of the system development so that all our courses are complete. Otherwise, you will keep in mind that this is not the only process. This is not the only approach. There are other approaches. They are better than this. But this is also valid. Another thing is that what do we mean by database application development process? This means that we develop the database for any system. And you will remember that the definitions that we discussed in the beginning were that a database model is a real-world system in the computer in the form of data. So the process is that when you represent the real-world system in the form of a database, this lecture will review the phases and steps of it. And the phases in which the database is directly related to the subject will be discussed in great detail. We will touch on the rest in detail. In today's lecture, we will discuss the first phase of the development process in today's lecture in the preliminary study of the system. What are the things involved in the database application development process? Let us look at it. Database design, application programs, and its implementation. These are the three things that I have just told you in the beginning. The books of the database are generally concerned with the emphasis on the first thing that is called database design. The things that are involved in your tools in this process are the emphasis on the books of the database. After that, the general characteristics of the database or the functions involved in it are discussed. The books of the database generally do not discuss the application programs and the implementation in such detail. Why? Because they are covered in the software engineering topic. Obviously, when we say that our database implements a real-world system in the form of a computer, if you have just the data of any system, obviously, it is of no use for the end-user, for the company, for the organization, for the system. Obviously, for the company, the application program that they are performing is of no use to them. That is more useful to them. The underlying database design that is being used does not have any concern for the end-user. Therefore, this is our database design. This is purely the concern of the designer or the DBA. In this course, as I have told you, for the sake of the completion of the course, the other two phases, the application program is a part of the implementation, I will discuss that as well. But again, our emphasis in this course would be on the database design thing. Now that we will study the database development process, basically, these three things are included. But our emphasis will be on those phases that discuss the first phase of the database design. Let us see. These are different things that we have already studied. There is a sort of a recap. A database design is a model of a particular real-world system. As I have given you the definition, I am giving you the reference that your database system designs a real-world system, models it, represents it, portrays it into the computer. It provides a picture of reality. The same thing should be simple and self-explanatory. This thing is being said about the database design. It should be that when someone sees it, it gets a picture of the system that it is representing. Another thing is that organizations keep coming and going. Let us say at some stage, if a DBA designer has designed something, it may be that the DBA designer is not there, and later on, someone who joins the organization wants to see it, understand it, or change something in it. For that, the design should be simple and self-explanatory so that they can understand it and use it. Let us move on. Now we will go to the database development process. In this, I am showing you a special approach to the database development process. The first is the preliminary study. The purpose of this phase is to understand the system, understand it, which you are designing and developing. This is the first and the basic step because without understanding the system, its functionality, process is involved. Without that, there is no question that you can develop a system. Obviously, this is the first step of any system development process. After that, once you have understood the working of the system, then you ask your user, your customer, your organization, what do you want from the database system? What output do you need from it? What are their requirements? What are their expectations? Understand those requirements and expectations and now you analyze them. Then you feel that to fulfill these requirements, what data and what relationship between that data should be represented? That helps you to build your database design. The application programs, activities they have to perform. But the data that is required to run those application programs, that would be provided, that would be fetched from the database. The database design should be the way that all the users and all their requirements meet efficiently. So, this process will develop an idea that will be through the requirement analysis phase. Next is database design. To fulfill those requirements, you will design the type of data you want. And our emphasis of this course is basically on this phase. How do we design the database and what are its different forms? In this course, our main emphasis is on this phase. But as I have said before, for the completeness of this course, I will discuss the rest of the phases. After that, what you have designed you have to implement on some DBMS. And that is what we call physical design. So, as its definition is clear, physical design that depends upon the particular DBMS or the implementation of your database. Implementation. Implementation is its definition and its description. But from our course reference, we will use implementation to write the application programs within this phase. Because we have already designed our database. We have designed it physically by adopting, by choosing different phases, making use of that data in different programs to perform those activities that are required by the users of the system or of the organization. So, implementation phase is basically we write the application programs. And finally is maintenance. Obviously, like your electronics or your vehicles or mechanical things, every machine, every system needs maintenance. As you can see, your database system needs maintenance. What does maintenance mean? It means that you observe its day-to-day working. And this is something that we have studied in the functions of the DBA. That the activities for which it is written and its requirements are being properly fulfilled or not. And secondly, if you want to make a new application because there is always demand of new applications. So, whenever the user says to write this application, that is part of maintenance. It is different that for a new application you have to run the entire process again. So, this is a particular approach which is the database development process. Similarly, a similar approach I will show you briefly in the next slide. We will analyze the requirements of the user again. The existing system and the requirements of the user are also included in these two things. After that, you develop a conceptual model. This is something that was not discussed in the previous slide. But this step, developed conceptual model, which I said in the design phase in the last screen, this thing is included in it. You have to understand that the first two phases which I said preliminary study and the second was analyze user requirements. They both were included in the first phase, analyze user environment. The database design is included in the development conceptual model. There are some things that are showing here that your conceptual model when you develop it, it is quite possible that during this phase you have to go back to the previous phase. You meet the user again and ask them what are your requirements? Explain them or discuss them again. That is why an arrow has been shown from again the development conceptual model on the environment analysis. Next phase is map conceptual model to the logical model. Again, this phase is also a part of the database design phase of the previous slide. This means that what we said in the database design was two phases. One was conceptual model and one was logical model. And these are the things that we are going to discuss in very detail because this is the crux of this course. This is the core of this course. How do we develop a conceptual model? What happens? How do we develop a logical model? After that you select a DBA. In the last slide you will see straight away physical design. As I told you earlier physical design depends upon the particular DBMS. The phase is shown explicitly that after developing a logical model you select a particular DBMS. Next is again developed physical design. The DBMS you have selected you will use your database for physical design. In this process there may be some requirement there may be need to go back to the conceptual model level to make the things confirm or to clarify any other ambiguity that may arise during the physical database design. Next is that you implement your system and again it involves writing the application programs. And in that you can do this activity in parallel. By using your DBMS you are designing your physical database in parallel with some dummy data with dummy design to start the application program. But it often happens that this activity is after the physical database design. Finally you test the system and after the test when you found the system working properly then you implement the system which you developed. But as I said the routine maintenance is the same thing that if there is any problem when you deploy it or implement it then again you may have to face it quickly or thoroughly from the first phase. Secondly, if there is a requirement of a new application then your existing system is running your developed system is running and to enhance it to change it you may have to go to the first phase again and from there you have to restart this process. So here we have briefly discussed the development process and mind it this process is correct it is applicable but the better the process you will study other courses and you will adopt it as a development process but the design part that we are studying here will be applicable there only. Let us go to our next slide. In this now we are going to discuss the first phase of our database development process and that is that you have to analyze the existing system. What do we mean by existing system? Existing system means that system that has been told to you to computerize that system that has been told to you for example you are told that there is a bank you make the entire database there can be many different systems for example there is a different system of loans the same way your accounts are different these are all different systems. Now the possibility is that either the company or the organization or your client can say that we design a particular system for example when we open our client's handling system we just make the database. The second possibility is that we automate the entire database. So either way the first thing is you have to understand how the existing system is working. Another possibility of this can be that the first part he was working on first he made two or three systems he said that he wants all of them. So did you want to patch them or attach them or make all of them Anyway in any case you have to understand the existing system and its working. So the first phase is the same objective that you understand its working and after that you have to understand the user's requirements because on this basis you have to understand it. Now we are going to discuss the preliminary study phase which tool we use and how we use it. But the first question is why do we use the tool? The tool we use basically is the data flow diagram and briefries are also called DFD. Through DFD the existing system you can use it to describe the functioning or the flow of the data Why is it needed? Why do we show it graphically? The reason is when you represent something through graphics or symbols those graphics and symbols they have got some specific meaning they are simple figures very few in number and you use them to describe your system and by keeping it in front of you you discuss the working of the system with the user of that system with the organization because it is necessary that you both agree on the things that is what the system is doing they have explained it to you but we have to make it sure that you have understood what they have described that is why they describe in the form of paragraph they may mean different to different people that is what I am talking about that can mean something else that is what I want to convey but it can mean something else to the listener especially in technical matters if we want to convey what we want to convey if we want to convey then if we keep moving then overall the picture will be very different from the actual picture that is why this is recommended that the understanding of the system is expressed using these graphical symbols we will keep them in front of us and while looking at them the user who is using the system will tell them that this system has this process how these people are involved and one thing is that this tool the DFD is so simple even the user a common user can understand it that very well and if he cannot understand then there is no need to understand it you draw it make it explain the working of the existing system using this tool and while keeping it in front one benefit of this is that it gives you a discussion point it gives you a central point on the basis of which you discuss your understanding with the user of that system one thing is this second benefit of this is that if someone comes to your place to do a job they will take over and they want to change that system so it will have to understand the working of this system so the DFD this will be able to explain it working of this system so this is the reason this is the need to use the tool to explain the working of the system let us see what the DFD is data flow diagrams the DFD represents the flow of data between different processes within a system any system you take different activities are performed different processes are involved now the process is the precise definition in the terminology of DFD we will read ahead but in general you can think that the activities that are performed in any system if you talk about a banking system then the account opening is working there there is a system of account handling to open the account to get money from the bank or to collect money these are different processes that are involved in the system in the banking system so the data flow diagram the DFD tells that in a system different processes are involved and in that people are involved and the data that flows here the information that flows here how does it work these are different characteristics of the DFD it is written that simple and intuitive not focusing on details is simple, there are not many symbols so that it does not get too complex and it describes what users do rather than what computers do, the processes in which the users are involved mention them the limitations of this are that it only focuses on the data flow the basis on which you decide that there is a decision for example, there is a process or this process you will show that after this process there will be one of these two processes but what is the decision or that one what is the decision that you do not represent in the DFD after that the different symbols of the DFD are there which symbols do you use the first symbol is data flow what is the purpose of this these are the pipelines through which packets of information flow and data flows are represented with the help of arrows arrows are labeled with the name of the data that moves through and this is the symbol of a data flow there is a head on which the arrow's head the data is moving in this direction from the tail of this arrow the data is moving towards the head of the arrow and the second thing is you will label this arrow label it so that the data flow is what is the data the second symbol is data store data store is basically a store a collection a repository where the data is stored static data means that this data is not frequently changed it is fixed this means that the data stores you store the data that you want to use for processing if you use it only in a process if there is no future use you will not store it but the data that is likely to be used in future for further processing you will store it in data stores or files and this is the name which is normally a noun and this is the symbol that you use for the data store after that your process the process the process could be very little very small activity or it could be a huge big process so any activity where the data changes from one form to another form and it is not necessary that there is a big change in the data for example if your data reaches a form in a process somewhere in a section and in that section they only checked if the form is correct or not if the form is correct they transferred the form to another section although this section did not add anything did not change the form but at least they have verified that the data is correct and the data you had before now it has become a verified data so at least it has changed this can also be called a process it is not necessary that the process changes or adds any activity, any process on the data where the data changes its form this is a process and how do we represent it we represent it either with a circle or a round an edge rectangle as you can see you can use any symbol but normally it is not recommended that you make a diagram and use both of them it is not possible you can choose one of them which is convenient for you and use the same symbol in all the diagrams when you use this process symbol in DFT in that each process has a number a number is given on it what is the principle of that number how do we do the numbering we will read this later in that you do not add any name it can be a verb or a small phrase but obviously the whole story cannot be there it could be 2 or 3 or 4 words and that is all so you have to identify the process and when you have a high level system then you can mark it as non we will look at this example and this is an example how we write the number in a process symbol and the name of the process where the process is written you will write the name of the process and where the number is 1.0 you will write the number of the process but we will read the numbering technique later apart from this there is another symbol in DFT which is called external entities external entities we call the source and destination of data that is your external entity either generates data or accepts data apart from this there is another question why do we call them external entities in that normally we suppose by making DFT we consider the system as something that is serving a particular purpose for example if we talk about an educational system then the activity processing of the admission system we consider it as a system after that anything interacts with it whether it receives data from it or any part of the system provides the activity of that system we call them external entities this means the word external entity does not mean that it will be something outside of your system or outside of that organization anything it can be an entity it can be something else it can be another system which is going to understand our system and ultimately what we have to develop is that data either provides or accepts data that is called an external entity the symbol we use is a rectangle apart from this another symbol used in DFT is a collector collector does not have any processing it only uses where we have to show multiple directions and from that it only goes in one direction there is no processing involved it just collects data from multiple directions from multiple places from multiple symbols and then it transfers the data towards in a single direction and the symbol used for this is this the round side on this side you will place multiple arrows maybe 2, 3 or more and the flat side or any other entity will go from here the same way separator does no processing but if you want to accept data from one side and want to place it into multiple directions then you use the separator symbol and this is the same the flat side it will receive data from one side and the round side will transfer the data then it is a ring sum operator this is a operator that will show where if there are multiple directions and from those directions it will flow data in one direction in which it will flow that is now the concern in the DFT but where it shows that these are multiple directions and for example it can be placed in front of a separator it can be placed in front of a separator but if it is going in multiple directions but if it goes in one of those multiple directions then along with that you place this symbol the same way the AND operator means that you show multiple arrows or data flows and when you want to show that data will be moved in both the directions so between those arrows you place this symbol that these are the two directions and from these the data will flow dear students so far we have studied different symbols that we use in the DFT now we are going to discuss what are different types of DFTs there are basically three types of DFTs and obviously there is a specific purpose of developing each one of them the three types are level 0 level 0 level 0 and the third type is the detail diagram now we are going to study what are these diagrams what are the purposes and how do we make them context diagram context diagram has a single process or a single system or a single process depends on the system or you can understand that the whole system as a whole, as a single process or a single circle or single bubble is used and no process is involved no data store no symbol is involved but a single process single system and its interaction with the external entities the context diagram shows the system as a whole plus its interaction with the external entities no processes no data stores in the context diagram and the name is written as a noun or a phrase it shows context only input and outputs but the inputs and outputs are only from the external entities obviously external entities are not on the data storage and one thing is when you are developing the context diagram then you will not show any data flow between the external entities themselves every external entity it will interact only with the system any data flow will be out of an external entity to the system or system to the external entity but not between two external entities here is an example of a context diagram as you can see there is a symbol which is a process symbol here you are seeing the name of the system that is being discussed that has to be developed this system is your purchasing system apart from this there are three different entities which are suppliers suppliers that could be a single person material planning department the entire department as an entity is shown here it is not a person it is an entity the receiving department is not a person it is a complete department it means anything that provides data to the system or receives data from the system is considered as an external entity in the terminology of the DFT apart from this you will be seeing data flows now your external entity is either providing the system or receiving it for example if we look at supplier entity supplier entity provides an invoice this is a form of data that flows from the external entity supplier to the system the system is shown as a complete system as a whole the system provides to the supplier it orders the second thing is that it generates payment from the system one thing if you look at where the purchasing system orders it and the payment is going but the purchasing system does not receive items from the supplier that means the supplier will give the purchasing system but the supplier will not supply the items although the supplier is receiving order from the purchasing system but it is not supplying the items to the purchasing system the payment to the supplier is being made by the purchasing system when you study the system you will realize the particular system that we are considering now what are the functionalities that are performed by this system if you see here it is shown as receiving department now receiving department it shows confirmation of receipts it gives the purchasing system what does it mean the supplier that supplies items to the receiving department and the receiving department we said that the two entities cannot come directly to the data flow in the context diagram so it was not shown here but it is possible that you are getting the understanding of this system that your receiving department that will give a confirmation of receiving to the purchasing system and on the basis of that the purchasing system will generate the payment will issue the payment to the supplier if you see the activity of the purchasing system from where your material planning department that is the department that receives the requirements from different departments and that the purchasing system sends the requirement of the material and after that the purchasing system starts its activity with the supplier this was an example of the context diagram let me show you another example of the context diagram in this diagram a university's admission system as you can see through a process symbol or bubble you have shown the system itself apart from that external entities interact with the system for example if you look at the dean entity the dean entity asks for faculty load sheets i.e. what is the workload of each faculty member similarly the dean entity requires the class count the class in which you have admission how many students are there if you look at the faculty members that is also an entity so from that admission system it needs the list of the class the class in which the faculty member has to teach how many students are there your admission system will supply the faculty members if you look at the registrar he will tell the admission system that which course we are going to offer in this semester and similarly the students' data will provide them similarly the students will request your admission system to enroll in the class and similarly your admission system will be accepted by the students so these are the two examples of the context diagram and you can see the basic purpose of the context diagram is that the functionality of the system from this point of view the external entities from which it interacts and the data flows between the system and entities Dear students we have studied the context diagram after this we will discuss the second type of context diagram called level 0 or level 0 diagram it represents the entire system and remember the system in which you make the DFT level 0 diagram will be included because this entire system represents the working level 0 diagram it is possible that there is a system that does not involve any detailed diagram but the context diagram and the level 0 diagram in the very extreme cases I won't recommend it but really if you have to avoid you can avoid context diagram even but without the level 0 diagram there is no DFT now the thing is that the level 0 diagram it represents the entire system its processes its entities all of these are represented now there is a technical question the depth the detail in the level 0 diagram what should be two things 1. the size the volume of the system it depends on that 2. on that designer who is developing this diagram because if if you have a diagram of the system for two different people the level 0 diagram the depth the detail the same if there are two different systems and the same person is developing the level 0 diagram for two different systems the level of depth will be different you have to maintain a balance what do you mean that if you have a very big system and if you try to put too much detail in the level 0 diagram this will become very complex then it will become difficult to understand on the other hand if you reduce it there will be two losses one loss is that the diagram will not portray enough information it will be much useful the other thing is that against the detail diagram you will have to keep a lot of depth so there is really no hard and fast rule that the level 0 diagram how much detail should be how much material should be what should be the size it is totally dependent on the system understanding that diagram let us discuss what are the ways to make the level 0 diagram what is its methodology the first phase to make the level 0 diagram is that the diagram you are going to make you can identify different modules and you start showing those modules repeatedly then in the appropriate places there will be a language in those modules how can that link be created it can be through entities, processes through data stores it can be in any way so the choice you make is that you first draw the entities involved after that write the processes involved and then link them and in this way the data stores involved you can make them and when a module is represented after that you take the second module the third one in addition what we have to keep in mind is that what we write the process number in the symbol of processes there is a special format its format is you give it a number like 1, 2, 3, 4 you give it a number and after a decimal you give it 0 that is your level 0 level 0 diagram the process you have always 1.0, 2.0, 3.0 in this way there will be a numbering it depends on whatever process you have represented in level 0 diagram there will be some processes that you have shown but the detail is too much if you show the detail of that process in level 0 diagram it will have the same problem that the diagram will be very complex which will be difficult to understand so you do that the big process with a single bubble with a single circle you show your level 0 diagram but the detail of that process you explain it further in the detailed diagram and one more thing is that you can have just one context diagram for any system you can have just one level 0 diagram but you can have as many detailed diagrams as you like as you need in a system as you told that you have to label your data flows and one thing is that whatever data flows you show you will never show external entity to external entity normally it will be that you generate data from an external entity it goes into some process and if data is transferred to another external entity or any data store it can be that you can transfer data from one process directly to another without sending it to any other external entity this is a general rule which I have explained how we make a level 0 diagram this diagram is an admission system of the University we make a module for this we identify application or applying one module the second module we identify is processing of the applications and the third module we identify is generating the admission list so we identify these three modules first we represent application process module as you can see we represent this module applying application process this module we are showing how our processes are involved and finally this module which displays or issues and how different modules are linked at different places and they have represented a whole system and especially the number of processes note that it is from 1.0, 2.0 and in the level 0 diagram the process number will always be in the same format Dear students I have shown you the example of level 0 diagram you must have understood about the level 0 diagram or in general about DFDs keep in mind that there are no rules or criteria for DFDs the rules to make DFDs whatever diagrams you have the basic objective is that they are self-explanatory first you are self-clean you are representing what you can understand about the system the second thing is that if you see any other person or any other person you should understand what you have shown the purpose of DFD is to explain the processes of the system in today's lecture we have discussed the processes we discussed them keep a special process in mind apart from that the first phase we discussed the requirement analysis and the tool DFD we discussed the two types of diagrams context diagram and level 0 diagram in the next lecture we will discuss the DFDs see you in the next lecture Allah Hafiz