lecture on networking and HTTP. This lecture has the intention to cover the basics that are needed to understand how the internet works and how requests travel in the World Wide Web. And that knowledge is at least on a basic level necessary to really understand what we're doing in web development. It is quite abstract, so you'll get much more in-depth knowledge when you take the networking course, but this is sort of the essential thing you need to understand what's going on. What we'll cover are networking basics. So what are hosts, what are IP addresses, requests and responses in the web, and a little bit on the TCP IP protocol. And then in the second part of this lecture I'll cover the HTTP protocol, which is the protocol that really runs the World Wide Web that you are using every day. The learning outcomes are three that are official and then sort of a couple of unofficial ones. So you should be able to summarize what HTTP requests and responses contain, what they do. You should be able to list different methods and their purpose, and finally explain the features of different HTTP methods. And we'll get back to that. Now in the official syllabus there are no learning outcomes on the networking, so these are sort of unofficial, that you should be able to distinguish what the difference is between the internet and the World Wide Web, explain IP address structures, and summarize TCP IP. These are not really course learning outcomes, but as I said they are somewhat necessary to understand what's going on. Now the book we're using in this course does not cover much on the basics of networking on HTTP, so there is not a dedicated chapter there. There are some smaller explanations on client server on HTTP response codes and on the HTTP methods in chapter six in the server chapter, but these are very brief. And they are needed in the server side part, which we'll get back much later in this course, so you don't really need to read in the book for this course. And then there are a number of resources which they are all not exam relevant, but they are the official documentation for the different things. So the RFC 122 or 1122 is the technical description of all the different layers of the TCP IP. So it's really a description of how the internet works really. HTTP on developer Mozilla gives you a good overview of HTTP, so it's just a basic overview, but much more digestible than the standards and then 7231 are the official standards for HTTP, if you want to look into that. And then again, there is HTTP status.com, which gives you a brief description of the HTTP response code, so that's something we'll go into later. Now, as we discussed in the first lecture, the World Wide Web was invented by Tim Berners-Lee in 1989. It was public from 91, and we said it contains hypertext, hypermedia, all of these things. But then, of course, the question really is what's the difference between what I wrote here, the World Wide Web and the internet, because nowadays we really discuss those interchangeably. We use those however they fit, but they are really different concepts.  So this is really all about the hardware. It's computers, like your laptop, your mobile phone, cables back in the days. Nowadays, it could be wireless, but it's all about how are things connected physically, and how do I get information from one computer to the next. It's sort of the architecture underlying everything. The web, then the World Wide Web, is the information space. So it's sort of all the documents, all the pictures, all the videos that you can access somehow, and that's really the difference. So on the net you find computers, that's the hardware. On the web you find documents, websites, and so on. So it's two different things. And the first part that we talk about is the internet. So a contraction of interconnected networks is really the global system of connecting computers. That you can access a picture that is lying on the other side of the world on a computer in San Francisco or in South America or so. And this all started with the so-called ARPANET, so that's the predecessor of the internet, which was originally a defense and military thing. So all of this was originally funded by the DOD in the US, and the intention was academic and military. So it was really all about exchanging academic information, for example data from experiments or military information. And already then something will go back into in much more depth. Back then already we used TCP-IP, so this is a combination of protocols to basically make sure that your information travels from one computer to the next. And this one is a nice little map of the ARPANET network, so that's in 73. This is a map of essentially the internet. So what you see here, the round circles are computers. So you see there's one in Hawaii, there is one in Stanford, there is one in University of California in Los Angeles. And then these are sort of the internet, the networking stations in a way, the cable shacks where everything would be connected. So this is really a logical map of how the internet looked like. And as you've seen it's pretty small. It's just a bit of the US and nowadays good luck trying to draw a map of the internet. But that's the background. So it has evolved from a military academic thing to really a worldwide free open infrastructure. Interesting is of course that nowadays we have a lot of countries, Iceland being number two here, where almost everybody is connected. The reason I show this map or did this figure is really to give you an impression of how this is in other places. Because if you look at 2017, then you see that we are in Europe, we are at 80%. So you already see the internet use on average is much, much lower in Europe than of course in Iceland, only 80%. If you go to Africa you're at 21%. So there are interesting things here in the sense that whenever you design your applications you should consider this that there are 20% in Europe, there are almost 80% in Africa that don't have access to it and that of course gives rather big implications. And that's really the societal dimension of web development that it's something that is not accessible to everyone yet. In Africa most likely the number has increased dramatically because an interesting thing if you look at it is the development here that you have a tenfold increase over 12 years. So it's quite a dramatic increase compared to other things. For example Europe has gone from 46 to 79, so it's not even double. So this is also where you can expect a lot of development in the coming years. But this page, this slide is really the message, keep this in mind when you develop your applications, who has access to it. Now the internet we discussed is a connection of computers and the question is how does it work? And what it really runs on is a protocol stack, a number of protocols that are called TCPIP and their purpose is to address and route data. That means well you have to have an address to send something over the internet. You have to know where it's going. You have to know how you route it, how you direct it to the right place. In many cases like when you watch a video, this video for instance, you have to segment it. You cannot send the whole thing in one piece but you have to break it down into smaller packets and that includes a lot of work because you somehow have to make sure that you get those packets together again. You have to make sure that all of them arrive and so on. Then whenever you write your applications, you somehow have to use this so it should be simple. Not everyone that creates a website for example can know all the details of TCPIP and we have lots of errors in the internet so it has to be reliable. For example, the most common thing nowadays is we have Wi-Fi and a connection over wireless is always error-prone so it's easy to lose information. You have to make sure that everything arrives if something gets lost you send it again and so on. Finally, you have a structural of the internet so not everything is in the same address space but you somehow segment the whole thing that you have subnetworks. For example, the university here has a subnetwork just for the university and then you have everything outside. A good thing about the internet is that all the standards are open so there is a task force called the IETF that discusses how to evolve the protocols, how to change them and they are published in so-called Request for Comments. These are the RFCs and that's where you can see all the standards. Many other standards are not open. For example, many of the ISO standards you might have heard of you have to pay to get but the IETF standards are all openly accessible and maybe that's a good time to actually look at one of them just to see what I mean. You can just go to this website and you'll see that you have the requirements for internet hosts communication layers. This is the specification for essentially how the internet works and the RFCs are always in this kind of format so that they look like it's an old-fashioned type document but it's really all you need.  That's good. It's not very good to study because those things are long as you see. The standard alone has 112 pages but of course if you want to write an application that works for all of the internet you have to know the details or if you write something for the IP protocol you have to make sure that you cover all the cases. So that's really when you want to look into there because you get all the details. For example, how is a machine addressed, what's the address and so on. So those are the the RFCs. We might use them now and then but now we get to the question how do we actually do requests in the internet because what I can do, what all of you do many times per day is request information from the internet and a typical thing I might be doing is I am on my computer, I open my browser and I say go to Google. I want to Google something and I press enter and you all know what happens. Ideally I get the Google front page and the question is now what happens in the background. What happens in the background is that my request is going through a number of machines all over the place and at some point they arrive at Google and these machines are at different places. For example here you see ru.is so that's most likely that's a computer that is standing in the university. Here you have something that's called Nightholds Week so that's probably an Icelandic thing and again it's .is so it's still in Iceland. Technicarder so it's same thing and a computer in the internet I probably forgot the s here but it's most likely it's is. Then there can be many other computers in between and at some point I have something that is really hard to read.net. This is as far as I remember it's already a Google computer and then I'm at Google so somehow my request from my machine in Iceland travels through a number of computers through a number of cables or Wi-Fi to the target host to the target computer and that one then of course sends the information back. Now we can look at this so in the command line you can look at a request by using the trace route command in Windows it's traceRT I think but I could say trace route Google so I want to know how is the route from my computer to Google and when I press enter it does the whole process so you see that it says okay the first step is going to this machine here. The second one is going to this and here is something at the ring road so it's all somewhere in Iceland .is and then here in Nordu.net is maybe already some computer that is not in Iceland. It says Ray so maybe that's Ray Kjavík but then UK is probably a machine in the UK so you see that somehow this request travels through different computers and that's really what I've depicted here in the picture. Now what this is really doing is that I send the request to google.com I press enter on my browser the request is routed so it's somehow directed via a number of servers a number of computers that are in the middle they intermediate and then the response from Google comes back to me. An important thing is that routes can differ over time so if I do the same request again tomorrow it might go a different way and also the response from Google can go a different way so it doesn't have to be exactly the same so which route I'm taking doesn't really matter as long as it arrives and the same goes for the response and how all of this works so how my computer knows that I have to go here and so on this is handled by TCP IP by the protocol stack and that one also handles for example if something gets lost along the way that I'm sending it again. How does this handle is actually quite complicated and this is part of the networking course so we just do a small excursion here but what you typically have are two so-called hosts so a host is basically a computer that has information and in my case host A would be my computer I want to get to Google and host B is the target that's google.com and in between there are so-called routers so there are machines that direct my request and the data then flows in a pretty complicated way so you are in your application I am in Firefox for example and I type google.com and this request is then broken down to different layers and sent over the internet and then it's sent to a target application so in this case it goes back to my browser but there are a lot of things happening in between and this is something that can be discussed in much much detail so what I'm doing really here is an is an application request in this case an HTTP request in my browser I type an address then this request gets broken down to the so-called transport layer and the role of that layer is really to do the addressing so it makes sure that there is a connection between the two computers it makes sure that my packets get sent in the right way and it makes sure that everything arrives that's the role then we can go down a layer further we are on the internet layer and that's the addressing the routing so it's really addressing individual machines which address does my computer have which address does the computer here at the university have which addressed us the google computer have and how do I take this way and finally we have the so-called link layer the lowest level that's all about the hardware so as you know you can have a wi-fi connection you could have a bluetooth connection you could have an ethernet a cable connection you could have a fiber or satellite connections there are lots of different hardwares in place and the link layer has the role of handling these things so that it doesn't matter whether your computer is connected with a cable or with a wi-fi or with a fiber so that's the link layer and we won't be talking much about this layer again that's something for the networking course so we start on the internet layer addressing and routing and that's what the ip protocol is all about now what you see here is exactly the same i've shown you before the only thing is i've replaced the names of the servers with these numbers and if we go back to my console window you see the same here so here you have the name and in brackets you have an address and this is the so-called ip address they usually look like this so they have four blocks separated by a dot and the role is really to identify machines so you have this number you have this address to identify a machine uniquely and the host name so the real the name i've shown you before is really just something that is used for for human understanding so if it says google.com that's because it's much easier for me to remember google.com compared to this address here so host names are just for for human understanding but in practice in the machine they are translated into an ip address this is done using dns that's not so important here just so hey you have seen it so for example google.com has the ip address 216 58 211 110 and what you can see is you can use these as well so if you're out of some reason if you prefer to remember this number instead of google.com you could also go to firefox and just type in this number and it will also bring you to google and as you see the the browser has replaced it automatically so it's really interchangeable it's just that we are much better at remembering names than these kind of numbers there are two different formats we just look at ip version four here but ip version four is four blocks of eight bit numbers so numbers between zero and 255 and they're separated by a dot so that's an an address and if you do a bit of combinatorics on this you get that you can have four billion possible addresses so that's all you can have in the internet some of them are reserved for example you will see a lot in this course the address 127 001 this is always the address that points to your own local machine so whenever you enter this you try to access your own machine now four billion sounds like a lot but this is actually a problem because with the whole iot development internet of things we are planning to have about 50 billion devices connected to the internet in i think it's 2020 or so so already now or at least in the near future so these addresses are not enough we need more and that's why a couple of years ago they released ipv6 version six that has an extended address space so it supports much much more addresses enough to i think enough to address every atom and the universe or something like that so it's a pretty crazy number but it's it's basically to ensure that in the future we'll be able to grow the internet without running into problems because every machine has to have a unique address otherwise we cannot connect to it now the interesting question is if i have the address so i know that this is for example google how does my computer or how does a router know where to send my packet where to send the request and the answer to that is something that's called a net mask so that's an additional number that is required to to identify whether the current ip address is in the same network or not and what you see here you have the address 216 58 211 10 slash 24 and this slash 24 is the network mask and it basically says the first 24 bits in this address are the network so they identify the network and then within that network the remaining bits in this case we have just 8 bits left identify the machine and this way a computer can calculate okay if i know 24 i can say that 216 58 211 0 that's the network so this is sort of a sub network of the internet and in this network i want to get to machine 110 and now the router can basically say that if my network address is different from the request then i'm in the wrong network i have to send it outside i have to send it to the internet and that's exactly how routing works on a very basic level so a router always knows the own network and it knows some other routers somewhere in the internet and whenever it gets a request it basically checks is it in the same network and if it's not it sends it out it sends it to the next router if it is in the internet then it has a list of all the computers that are within the same internet within the same network so on a very basic level that's how routing works you check am i in the same network yes or no then just to mention this there are some ip network numbers some ip ranges that are reserved for private networks and i mainly mentioned them because you might have seen them so for example if you have a router at home for your for your internet very common ip addresses are 190 268 0 so that's that's the typical network that you have at home and then there are two more that i used usually for for larger private networks so for example here in the university you see that we're using this 10 dot and then the remainder is the machine name so those are private networks and if you see those you always know that there are within sort of the within the organization at home and so on so if you check your ip address at home you'll see that most likely it's something like that 192 168 0 okay so what we've discussed so far is that i want to send a request from my computer to google and we have a bit of terminology here so the first thing is my computer and the target is usually called the host name so that's something you should be knowing i mentioned it already so those are the machines where the request comes from where the response comes from then you have a so-called ip address so that's just the host name translated to a number that's the real address that the computer uses and you have a lot of servers that are in between when you send the request so it's routed via those intermediate servers and these routes are basically the connections between the computers and as we discussed they can change over time so maybe the next time you send this request the response goes directly over here also intermediate servers can have a lot of different roles so they can be routers as we already discussed so computers that basically direct the traffic in a certain direction then make sure your your packet your request reaches the target they can be proxies maybe you have heard that so those are machines that for example filter data make sure that you're authenticated that encapsulate so they hide part of a network they cache that's a very important concept so they basically try to reuse data so you don't have to send the same request all over again so those are typical things for example a typical thing you have in companies what proxies do is they might disallow certain connections so for example the company does not want you to be on facebook all day so they block it that would be the role of a proxy to say whenever you send a request to facebook we instead redirect you to google or we send you to a page that says not allowed or something like that there are computers that are called firewalls that are essentially security things so they make sure that there are no attacks or that if you if you get a response from a malicious place it's blocked or so on there are machines that are load balancers as the name suggests they they try to balance the load over multiple computers so google again is a good example they have lots and lots of computers that answer your search requests and at some point there is a load balancer that says okay if the first computer has too much work to do send it to another one and then finally one important thing is whenever you see that in this picture i'm using the the picture for a machine for a computer for a server but an important thing to understand is that on one computer on one physical machine there can be several server processes so basically several applications running that fulfill a certain purpose so the server is usually used as a name both for the physical machine but also for the software running for example my computer i can have a mail server and at the same time i can have a a web server that's no problem good now this was all about machines computers now we'll make a very similar example in the real life in the non-computer life and that's about post so i do something very similar when i want to send post around an answer to it so imagine i'm sitting here at reikevic university and i want to order a new computer and i want to order it from apple in in the us um what do i do well typically i go to their website but i could actually also send them an old-fashioned i could send them a letter so let's say that's what i'm doing um and what i'll do is i'll send the letter to the internal post here so there's some kind of post system that makes sure that my letter gets sent the internal post looks at it and says okay this goes to us it's not within our own company it's not within the university so we have to send it outside the mail truck picks it up it brings it probably to some central post in reikevic they realize it's not within iceland so we have to send it via ship somewhere else it probably arrives somewhere in the us or i don't know where and at some point it arrives in in the us and it's sent via a truck to cupratino and it's sent to apple directly so that's typically how my letter could could arrive and you directly see that routes can change so it could also happen that my letter gets sent by post by airmail instead so then the route here is different and most likely also the point where it arrives is different so routes can change over time um and the response then apple takes the parcel sends it back to me and again maybe the parcel is transported a different way because it should go much quicker it's going by airplane instead of ship um so this is really exactly the same thing uh what i have down here is similar to my host name i have an address that identifies me uniquely hopefully uh i have these intermediates so here they're basically post offices all over the world that process my email or my mail sorry um you have routes different ways that your your parcel your letter can take um and it's really exactly the same so intermediate servers can have different functions you could have a post office where you sort uh you could have internal post for example uh which is similar to a proxy so here at reikevig university they sort out email uh that goes to different places compared to email to mail that stays within the university um you encapsulate so if someone sends to reikevig university to my address here uh you see that there is not my office number there so they don't know where exactly i'm sitting uh so the internal post actually has to do this sorting so there's some kind of encapsulation going on and similar to a proxy they might filter stuff so if i let's say i want to get a play by boy subscription at work uh my boss might show up and say well you know that's not the right place to do that so it's a similar way to a proxy for internet that they say don't go to facebook while you're here um and we discussed routes can differ so most likely the parcel is taken a different route compared to a letter um and there's a different speed if i'm using a ship or a truck or an airplane so it's really pretty much the same uh whether you're using the internet or the posts or the mechanism is quite similar ip addresses a net mask well uh the analogy here is really street name zip code city name uh if you write a street name only then you have no idea where to go because street names are really common in many places so it's not like your street is unique um so it's not enough to just have the street name you also have to check the city the zip code maybe even the country um and that's the way to distinguish whether you are in whether you have to deliver your your mail in the same city or you have to send it somewhere else so that's quite comparable to the ip address and to the net mask that you need two elements to really figure out where to send it okay so that was the the internet layer basically the ip protocol and now we'll dive shortly into the transport layer uh which as we discussed is about end-to-end connections so make sure that uh connections are established are canceled are the right order of packages is there and they are reliable and this is the role of the tcp the transmission control protocol um so what tcp does is it makes sure there is a connection while you're sending something it makes sure that your request is cut into chunks so if you send the video is put into a lot of small packets and send the way it makes sure that talking about videos for example that there is an order so we discussed that routes can take different times so it might be that your video information at minute two arrives before the video information at minute one so tcp then makes sure that these things are reordered so that you can actually watch the video tcp has a way of checking the correctness so maybe it has changed because of inference in the cable or so on things might get lost because the wi-fi connection was bound and this is all handled by tcp so making sure that in the end you get something that is proper the puzzle is essentially reassembled uh there is an alternative to this so just that we have heard it there's something called the uniform data protocol udp um and it's it's an alternative to tcp because if you read this you can imagine that this is expensive so it takes quite some uh computing power it takes time to actually make sure that things are correct that the order is correct and so on so instead people came up with a udp protocol which is unreliable so it doesn't care that much about order correctness if a package gets lost we don't care we don't send it again if things arrive in the wrong order we also don't care um and the main reason to have that is that it's quicker so in many cases for example if you're streaming video live streaming it's more important to be quick than to be correct uh and then you can say okay i i don't care if the video is a bit messed up in between but at least it's going quick uh so many times for example if you would use skype udp's preferred because it's simply quicker okay um so that was all we cover about how the internet works it's pretty basic but it gives you an understanding of what is happening uh especially since i'll talk a lot about for example hosts about the layers i'll use the different uh terminology so we should be aware of that now we go from the internet to the worldwide web and we said that the worldwide web is the information space so it's all about documents uh pictures videos uh items of interest so something you would like to have and to be formal we typically talk about them as resources so whether you want to have a website or a picture or a video the terminology says i want to have a resource and these are identified in the internet using so-called uniform resource identifiers so those are basically the addresses that say i want to have the wikipedia page on worldwide web for instance um resource can be confusing so if you don't really know what this means uh wait until we get to back end to the server side lectures it will become clearer for now if we talk about a resource you can think of a website an image or a video so that's fine that's really what we want to do um and to make this a bit clearer we abstract from all these intermediate machines we typically talk about the client server model uh so my computer i want to have google.com requests a resource and the server the target host responds with the resource um so instead of looking at the whole picture we talk about the client server model i want to have the wikipedia page on worldwide web the wikipedia server returns the right website or if something is wrong it returns an error and as we have seen uh this is of course an abstraction usually there are a lot of different servers involved uh there might for example be the web server there might be a database server there might be a mail server and so on so it can be many machines it can be different programs but to make this simpler we talk usually about this client and server and that's it for the network part so in the next part of this lecture we look at HTTP which is the protocol for the worldwide web so that's it for now


Oh Jay you see says anyone else no volume. I'm sorry Okay, I'm gonna go back through this again really quickly. Sorry about that. I think the The mute button was actually Pressed on my microphone. I didn't realize it. So I apologize All right, so Let me go through this really quickly general disclosure all book map limit limited materials information and presentations are for educational purposes only and should not be considered specific investment advice nor recommendations risk disclosure training futures equities and options involves substantial risk of loss and is not suitable for all investors past performance is not necessarily indicative of future results As a reminder the focus of my presentation is options order flow The impact of options markets on stocks and futures and the influence of market maker hedging flow on price action I have a two-step process for trading and the first is planning and I use positional analysis I look at how traders are positioned Traders and market makers are positioned in the options market and how those positions change from day to day to develop a thesis regarding the expected trading range and volatility for the day as Well as a directional bias and the second step in my process is Execution I look at real-time order flow in book map and real-time market maker hedging flow with spot gamma hero To confirm my thesis and for setups for entries and exits and this is something different a lot of traders use technical analysis or fundamental analysis and I'm taking a new approach here with positional analysis and Questions and comments are welcome Please post your questions and comments in the options dash Doug chat channel and discord and the chat and YouTube and I will be watching both and I will do my best to Respond to your comments and answer your questions and JECs. Thank you. Thank you for the notification Okay, so hopefully all is good now All right, let's get started and my agenda for today what I want to talk about first of all I want to go through a clarification There were a lot of questions yesterday About exactly what I'm trading and I want to talk a little bit about that So I want to do a Clarification about what I'm doing here what I'm trading and then we'll go over the news briefly the economic data Coming out the rest of the week as well as events Important events this week then we'll go through our positional analysis and then finally we'll talk about some setups So first of all clarification Okay, thank you J.C. Time stamp it so Yeah, we can bypass the three or four minutes of silence Okay, so clarification of what I'm doing here is I'm using the options market to inform all of my trades one of my key tenants for trading is that market is that options trades and hedging flow market maker hedging flow are key drivers of price in many stocks and Equity index futures and this doesn't happen All day every day, but I've seen enough to know that this is very often more often than not a key driver of Order flow and price action and one of the reasons is that market makers are in the Options market all day long hedging and they want to remain delta neutral So they are doing whatever they need to do buying or selling stock or futures to hedge their delta exposure and again this is a key driver of price action in many stocks and Certainly the stocks that are on my watch list options trades are key driver some some more than others and then as well as futures So when traders Buy or sell options and spy or spx for example Market makers hedge their delta exposure with ES futures And the same for QQQ when more when traders buy or sell puts and calls and QQQ Market makers are using in Q to hedge their delta exposure in Q futures So I use this information again for my planning and execution whether I'm trading stock shares of stock or SPX options or futures and there's a reason I I choose to trade shares or futures And I'll talk more about that But you can use this information to trade Any instrument that you want and there are again advantages and disadvantages you know the one big topic recently is the zero DTE options and You know again, there are advantages and disadvantages and I'll talk more about that and So again my approach is about using options as a basis for trading but not necessarily trading options only so actually let's take a look at an example now and This is this is Tesla and this is just something that I Just a simulated trade that I put on this morning and for those of you who may not be familiar with us this is a profit-and-loss diagram or risk diagram and I was just you know, this is just an example not saying that I did this or this is what to do You know as it turns out. It's not a good idea So this is the blue line. This is the options of a 10 March March 10th and I'll call 180 call that expires this Friday. So that's the next expiration for For Tesla so for Tesla and many other stocks Apple and Nvidia Those stocks have options that expire every Friday SPX spy and QQQ have options that expire every day so those are the actual zero DTE, but I just was looking at Tesla and saw this example and The reason I don't like to do this. So again the blue line is the profit and loss at expiration at the end of the day on Friday and this purple line so here is the The blue line that's the profit and loss at expiration and then the purple line is The profit and loss diagram right now and that will that will change during the day and the thing to notice here is this Data, I don't know if everybody can see this so I have taken price slices at The zero level the at the current level that's this line right here That's the current price level and then at plus or minus two dollars and plus or minus five dollars so what this is showing theta is the That's showing how much Thanks, JC. So that points out. This is how much you you're losing in time value Every day So the middle value is at the current price. So right now just holding this call You're losing a hundred and four dollars Per day is what it's showing right now And that's something that I just I can't overcome So that is I was trained to be an option seller So this is the penalty that you're paying for buying a Buying a call or buying a put and especially being wrong You need to be right and you need to be right fast For this to work out So again, this is showing that the Theta burn this is the extrinsic value of that option will lose Continue to lose value and at Friday afternoon this Purple line Will move down and become the blue line and that's right at the end of the day on Friday And so this option was Four dollars. Let me change that So at the time That I put this on again. This is just an example The cost of that call was four dollars and seventy cents. So that means that Not only do you need Tesla to increase to make money, but at expiration you need it to increase By at least four dollars and seventy cents just to break even Now that's the that's the disadvantage and that's the the trouble that I have with With buying a single option The advantage and JEC presented this yesterday is Especially with zero DTE options that that are not expensive. Let's take a look at I Have I Don't have any positions in QQQ. So let's take a look at QQQ. Take a look at an options chain here and This is the This is today So here for example, you're you're spending a lot less you're risking a lot less You know, let's say you want to buy and at the money call or put you're gonna be spending Less than a dollar. So you're gonna have Less than a hundred dollars at risk Okay, so that is but the advantage is That's defined risk. You know if you buy this let's say you buy this call for 67 cents and So your risk is sixty seven dollars and you could potentially make a lot of money if If QQQ increases and this shows you For every dollar that it moves higher, you can just look at the options chain and these are further in the money So if If right away very quickly before that Option decay catches up with you. Let's say if if price instantly jumps two dollars from From it's right around two ninety six now jumps up Two dollars your Call that you paid sixty seven cents for could be worth over two dollars So that's the potential and again the Risk is defined. You don't have to worry about it. You don't have to set a step law stop loss you can just Buy that option and set it forget it not worry about it. I would say that you know if I did this I would be willing to lose sixty-seven dollars To make two hundred three hundred dollars whatever your whatever your projection is so that is That is why I prefer shares and other structures so I want to clarify that again just for those of you Who may not have looked at a? Profit and loss diagram. This is the battle that you're facing when you When you're buying an option is this theta burn a hundred and four dollars a day To hold that option and that you know, that's again a hundred and four dollars and that will increase as time passes So a hundred four dollars today may be Hundred and fifty two hundred dollars today, okay, so let's let's go on now. Let's Let's talk about the news briefly so Yesterday Jerome Powell testified before the I think it was the Senate banking committee and he continued to testify today and This is After yesterday his testimony yesterday was hawkish and the market interpreted it as hawkish and notice the change in the This is the Fed watch tool from the CME and The current target rate right now for the Fed funds rate is 450 to 475 basis points yesterday the Yesterday, this was basically the other way around So that and actually this is showing the the end of day yesterday. So this is let's look a week ago so this is the This is for a 25 basis point rake height from 450 to 475 to 475 to 500 one week ago that was 70 percent and And the percent Chance of a 50 basis point hike shown here was about 30 percent. So 70 percent 25 basis points and 30 percent for a 50 basis point hike and that has shifted dramatically. So now the Chance of a What the market is pricing for a 25 basis point hike is now 23.6 percent and the Expectation for a 50 basis point hike is 76 percent So what? So a dramatic shift in expectations for the Fed funds, right? Okay And then finally the unemployment the employment situation report is Friday again. All right, so let's take a look at charts That's enough of Enough of that. Let's take a look at charts now let's go to book map and this is showing the S&P 500 futures ES and And before I dig into this chart, let's take a look at a larger time frame look at the levels on the charts This is SPX just showing price and levels and these levels are from spot gamma and they're Updated daily. This is provided in a think script to spot gamma subscribers and this is showing the key levels So there's the put wall and I'll talk more about these levels in just a minute and then up in this level Here's a combo level the 4,000 key gamma strike and then the 4,005 volatility trigger and I'm way up above still is the 4,200 call wall So those are the some of some of the key levels that are in play for today So that's a 20-day one-hour chart just showing a bigger picture View And let's take a look now at a one day one minute chart again and think or swim And this is just showing the levels that are in play for today and a little bit more closer view So the things to notice first of all this SPX 3974 level that was noted as support in the spot gamma am founders note Held a support at least initially this morning and then this and then the 4,000 level this Combo 3998 and then especially the 4,000 level was a resistance So those are the levels that are in play for today All right, let's go to book map now And I'm showing The same levels and more on my book map chart the first is the spot gamma levels and this is again from spot gamma the same levels and In book map cloud notes so that these are updated automatically and this is showing key SPX levels Like the L to 4,000. That's the SPX key gamma strike and then the combo L4 level That's a combination of spy and SPX levels converted to an equivalent SPX number and then converted to an equivalent ES number right now spot gamma is using a five-point difference between ES and SPX and this morning I just did a quick Calculation and it looked like it was about two and a half points to me So that is where I've drawn my levels in My column that my cloud notes So I'm showing here the spy 400 key gamma strike and volatility trigger and then the This is the 4,000 level where I calculated it and this is closer to the What we just saw on the SPX chart the again the SPX just touch touch that level and here if the if You were actually looking at the four thousand five level Price did not get up that high. So again, I'm using a two and a half point difference But we can see the same thing here in this chart 4,000 as resistance and that's SPX 4,000 and then SPX 3974 the level noted in the AM founders note here acted as support and it looks like Price has breached that it may be trying to reverse hire at this point alright, so that's the levels in play for the S&P 500 today and One thing to note is This is the this 3974 if you look at a traditional chart This is the initial balance low and there's a You know when you look at those levels, there's often often a reason for that And actually this is probably the fourth out is probably the initial balance high And there's a reason for that and here's the reason so, you know, you can use those levels or get to the underlying cause and Reason that those levels are the low on high and here it is All right, so let's talk about shifts in levels and There were Just a few shifts in levels Just similar to the last couple days shifts in the volatility trigger and zero gamma levels first of all Everything was down across the board today volatility triggers and zero gamma levels for SPX spy and QQQ and for SPX volatility triggered drop from 4025 yesterday to 405 today and Then spy volatility triggered drop from 4404 yesterday to 400 today and QQQ the volatility trigger Just had a minor drop from 301 yesterday to 300 today and the volatility trigger is spot gammas proprietary gamma flip level and that means that above that level Traders are and looking at an index now traders are short calls market makers of long calls and that is a positive gamma position and in this in a positive gamma environment they have to hedge against price to hedge their delta exposure and that tends to subdue volatility in a positive gamma environment and then on the other hand below that level traders are long puts market makers are short puts and That is a negative gamma position and they have to sell futures to hedge their delta Delta exposure as price drops and then they can buy back their futures as price increases and that tends to Increase volatility in a negative gamma environment All right. So again the volatility triggers both For SPX spy and QQQ all dropped as well as the zero gamma levels Otherwise, there was no change in the put walls call walls or key gamma strikes All right, let's take a look at the The gamma levels charts now and we can see where those levels come from All right, so here's the S&P 500 and this is the SPX and there's that 4,000 Key gamma strike or absolute gamma strike and that's been it's been like that for for quite a while That's just like with the largest absolute gamma and then the put wall is The strike with and that can act as support resistance or a magnet for price And then the put wall is at 3,900. That's the strike with the largest net negative gamma and that can act as support for an index and and sometimes for stock but You I guess more often than not especially within Index SPX by QQQ you expect that to act as support Again, that's the strike with a large is net negative gamma and Then the call wall is up here at 4,200 the strike with the largest net positive gamma And that can be expected to act as resistance and notice that is that's pretty small well out of play and notice here the dominance of put gamma Below the 4,000 level and I forgot to mention That what I'm looking at here. This is the zero line and above that line This is positive gamma or call gamma shown by the black bars and Put gamma or negative gamma below that line shown with the teal bars and this is market makers position So that is SPX Your spy 400 key gamma strike 390 is the put wall and Then the call wall Remains at let's see where it is 408 Which is a little bit unusual to be at a not at a five or a 10 anyway the a Lot of put gamma at the 390 and 395 level and a predominant There's a predominance of put gamma below the 400 level and call gamma Above that level and while we're on this on this page Let's take a look at the combo strikes and this is combining SPX and spy strikes and then converting that to a an equivalent SPX number and showing put gamma or negative gamma below and Call gamma or positive gamma above and here this is the right around this This is 4,002 and 4,014 and this is the the flip level and it's showing 4,006 there remember the volatility trigger Was it 4,005? Put gamma below call gamma above but more put gamma below and here spy Showing the same thing combo strikes converted to an equivalent spy number and here's the The gamma flip level at 400 which is also the key gamma strike and Again, notice the predominance of put gamma below All right, let's take a look at the NASDAQ now on from the NASDAQ. We'll just focus on qqq so for qqq 300 is the key gamma strike or the absolute gamma strike The put wall at 290 and that's pretty obvious the strike with the largest net negative gamma and Then the call wallet at 310 All right, let's take a look at data now and I always like to take a look at gamma notional and kudos to the guys in and discord for noticing this this morning JLA Carmo trades JEC and having a discussion about this noticing the the sharp increase or a decrease in gamma so SPX spy qqq gamma notional all became much more negative and then recognizing the potential for a Put Vanna rally given a spark to to fuel a move higher and so far today Whatever pal said wasn't was not that spark Okay, so gamma notional. This is market makers position on the gamma curve And this is SPX in the left column spy in the middle column and qqq on the far right column And again as I said these levels did shift Quite a bit more negative. So yesterday SPX gamma notional was minus four 44 today it has shifted to minus five sixty five Yesterday gamma notional for spy was minus thirteen twenty one and today it has shifted Quite a bit more negative to minus twenty three thirty six and then finally QQQ gamma notional yesterday was minus four twenty eight today. It's minus seven oh four and Again, this is market makers on the Position on the gamma curve. It's quite negative Indicating and we just saw this in the gamma levels charts that traders were long puts market makers are short puts and that That puts them in a negative gamma environment and they have to Sell futures as price decreases to hedge their delta exposure and then if Price increases and applied volatility drops they can buy back their short futures. So that is, you know That could potentially lead to a put Vanna rally and let's take a look at the Vanna charts now And that is this is a graphical illustration of that. This is for SPX Showing that as price decreases. That's on the horizontal axis Their delta notional will increase that's in the vertical axis and this indicates that Market makers will need to sell futures to hedge their delta exposure as price drops and they market makers want to remain delta neutral and The green curve that's the current expiration is showing how their Delta notional changes with changes in price and implied volatility and that's the Vanna effect the change in Delta with a change in implied volatility So that is SPX again negative gamma environment Your spy it's even steeper gamma notional is much more negative and here's QQQ so all showing the increase as Price increases as increase in delta notional as price decreases and Again, this is typical negative gamma environment meaning market makers need to hedge with price To hedge their delta exposure. All right, then finally This is my key gamma strike list and I just do this as a quick reference Note the changes in the key gamma strike for all the stocks in my watch list the e column is showing the key gamma strike from the Previous day and then this is the current key gamma strike for today. I color code these Green if it increased Red if it decreased from the previous day and one thing to note here is this is the VIX and The current key gamma strike increased So it looks like traders were buying buying calls in the VIX yesterday Calls or call spreads Okay, so that's my positional analysis given all this I develop a thesis for the day and normally I would use this and my thesis for the day would have been Probably neutral to bearish but with a pile speaking at 10 a.m. My thesis for the day would just like yesterday Wait on pile. See what he says. See how the market reacts. So with a big event like that, it's hard to I think at least for me hard to develop a thesis Based on information that that is available before he speaks Alright, so let's take a look at some setups and here. Let's start with the S&P 500 So chop and then finally price is moving lower. Let's take a look at something very interesting in Spot gamma hero and let's go back. Let's take a look at This is the S&P 500 so this is a combined signal of SPX plus spy calls and puts Transactions and if you trade the ES especially Even if you trade spy or SPX options This is typically what you want to look at. This is the combined signal of SPX and spy and this is what is driving the S&P 500 So let's zoom in on this chart now and the very interesting thing to point out We can this is looking at all expirations and we can Change that so it's just looking at Looking at zero DTE option So this is options that expire today and remember both SPX and spy have options that expire today I'm going to zoom in a little bit on the morning and I I posted this in and discord Increase this just a little bit to increase Viewing so this is showing that With these zero DTE options Traders are fading the moves So as price Let me zoom in just a little bit more as price increases and They start taking negative delta positions In zero DTE options so notice here price is moving up and Before our right as price is moving up. They start to take zero DTE negative delta positions with zero DTE options So when YouTube Ali asked what software are you using? I'm using two things so I'm using book map and And That's what we were just looking at and now this is spot gamma hero This is web-based and it comes with a spot gamma subscription and this is showing This is hero H I RO hedging impact of real-time options and What this light blue kind of blue green line is showing is Options trades and the market maker hedging flow So the white line is price And we can see as price is increasing Traders start fading that move. They're basically selling the high Here this price moves down a little bit they start to buy the low and Then as price increases they start to sell the high price drops and they start to buy Price drops a little bit By again And if you watch this carefully this can provide a lead effect So Ali says don't know much about hero if you're interested I Suggest you go to the spot gamma YouTube channel and search for videos about hero They have plenty Right now hero is web-based only and this is what I'm looking at And you can also just look at the their free resources resources in the on the spot gamma Website and you can read about hero as well The spot gamma Let me just type that in chat Yes, I'll a I spilled it correctly Okay, so this is showing the lead effect that these zero TT options have on price action in the S&P 500 and this type of action also tends to suppress volatility trapping price in a range and You know, there are a couple of couple of ways of approaching this actually many ways to approach this one is to follow them to To sell the highs and buy the lows once you establish that trading range for the day and we saw When we looked at the book map chart and the And the SPX chart and think or swim that that level those levels were clearly 3974 on the downside which could anticipate As well as the 4,000 level above good levels to buy at 3974 and Sell at 4,000 way whether you're buying or selling SPX options ES futures spy shares spy options however, you want to do it Many ways to trade the S&P 500 and you can also use more complex option spreads, let's say if a price was down at the low you could buy a zero DTE butterfly at 4,000 for example and you know have very little low risk and An asymmetrical reward if price moved back up to that 4,000 level and I I tried that just and we'll take a look at that In a minute. So anyway, this is what? What the zero DTE? options traders are doing All right, let's change this back to look at all trades So I thought that was interesting and let's go take a look back at bookmap now So, you know, we could be looking at that You know again that hero chart and then Knowing the range here 3974 to 4,000 Trading up and down in this range Let's just go back and take a look at at hero and see what what traders are doing now and just looking at the total signal so they You know this shows the same thing as well is that traders are taking positive delta positions at Down just below that 3974 level and price is now starting to move higher Let's go back to bookmap now And we can confirm that with with order flow somewhat here So more green dots these are market buy orders coming in and Helping to shift the the move higher and we can look back and see how order flow shifts From bearish to bullish just by looking at this volume dots That's buy minus sell so this is showing with these pink dots There are more Market sell orders than market buy orders pushing price down and then this reversal. Let me Change that Notice the reversal here this I'm going to zoom in a bit on this It's it's hard to see here. There's a blue number 750 you can see the iceberg order coming in So a stop run down to this level by iceberg comes in and that's also confirmed by this light blue line and then the the shift in order flow from bearish down to that level stop Kind of a stop run down to that level My iceberg comes in order flow shifts to bullish Back up to the 4000 level chops around a little bit Order flow shifts bearish again and price moves down Toward the 39 74 level so you're confirming the the signal in in hero with What you see an order flow here knowing these levels watching order flow as well as the hero signal All right, let's take a look at some other setups And remember yesterday these semiconductors were strong AMD and NVIDIA both are on my watch list. Let's go take a look at hero Take a look at AMD Let's zoom in separate outputs and calls So the orange line shows calls and a rising orange line means that traders Are Are buying calls Not doing much with puts At least in the morning. Let's zoom in on this So looking at the morning here Traders are definitely buying calls and that's driving price action. Let's go back to book map Nice uptrend and notice the Target at the 85 call wall And yesterday this you can expect this to act as resistance Yesterday, I did talk about a situation where a breach of this call wall can act as an accelerant And invoke dealer hedging and it looks like it did a little bit here But then price started to move lower As aggressive sellers come in again. Look at the green dots I mean the the pink dots. I'm sorry. So the shift from green to pink And price moves lower, but that was your first price target reversal at vwap reversal at the 84 and then this reversal here We're all good entries up to the Call wall target level All right. The next setup was Metta Let's go back to hero And notice how price has leveled off as hero Starts to drop price move slightly lower And also is that call wall target was reached Let's take a look at meta All right meta. There's a strong correlation between options trades hedging flow and price action And in the case of meta Traders were actually selling puts that shown by the rising blue line All right, let's go take a look at book map And multiple long entries up to targets at the 184 liquidity and the 185 liquidity Pretty choppy morning action a lot of deep pullbacks Looks like the pullbacks to vwap were the best And Microsoft Pretty choppy action wide range Let's go take a look at hero For microsoft and i'm going to zoom in on On this so that really confirming Short entry In the morning Long entry about 10 10 15 And then short entry But I thought the best Given the most risk reward was this setups here at these deep pullbacks As hero continued to rise and a pretty steady line there Let's go back and take a look at at book map So there's the those entries if you didn't if you didn't catch this first reversal Watching hero steadily rising And these deep pullbacks All right, let's take a look at nvidia And let me uh, it looks like there are a couple questions on On youtube So i'll he asked Yes, you can trade crypto With book map. This is not Not part of not one of my topics So all I will say is yes, you can trade crypto With book map. This is beyond the scope of my My webinar, but I suggest you go to the book map website and just search for crypto. There are plenty of crypto traders There's a question. How can you use book map to see if the move will push through? At loads or highs I'm not sure I understand that question Um, you know, I don't have any specific Answer for that just watching order flow um I don't know. I'll I'll have to think about that. That's something that uh, you know, again, just watch order flow if if And let's let's we'll go back to es here and see that You know here here you were uh, assuming this level would be support price broke through there was uh Here just look at the clues large stop orders Moving price through, you know, if I expect this level to act as support I'm going to look at And that's how I would look at it look at Uh, you know confirm that in order flow. So price continues lower And then starts making Higher highs. So at this point and also I'm looking at hero and seeing the hero line rise. So at this point, I'm Uh, assuming that this level although it didn't it price exceeded it a little bit Price did not rip lower So I don't know if that answers your question or not, but you just have to watch order flow to confirm that All right, the next one we looked at looked at microsoft. Let's take a look at invidia and again semiconductors are So I'm looking at I'm looking at order flow right now. This is book map in case you're not familiar And this is showing Uh, the order book the history of orders. So this is the order book right here a current order book c.o.b showing all the limit orders by uh by below price sell above And then this heat map for example The shaded area is showing the history of seller orders at the 240 level So liquidity levels So this is kind of getting at book map basics, which is kind of beyond Or a different topic than what what I want to talk about I suggest you go to the book map youtube channel and watch some of the basic Basic webinars attend the advanced webinars Ask bruce at book map ask these questions. This is pro trader this week Book map is having a pro trader webinar series next week. The regular series will resume And bruce Is the I guess the director of education and he conducts an advanced webinar Every day at 10 a.m. Eastern time They're also recorded and available on the book map youtube channel And he talks about that in more detail. So I look at these liquidity levels. First of all as a target So looking at this this morning I see price rising. We'll look at hero in a minute a couple of pullbacks to vwap And this liquidity level up above at a big round number 240. I look at that as a target price seeks liquidity All right, let's go take a look at hero now So that's microsoft. Let's go to Nvidia and very strong confirmation Correlation between options trades Hedging flow and price action All right, let's go back and take a look at book map And notice the the fairly deep pullbacks, but pretty much a steady uptrend in hero, especially until about 11 a.m All right, so let's go back to book map now. So there's Nvidia Hero was strong rising pullbacks to vwap and round number levels With the liquidity target up above at 240 and 241 Let's go take a look at spy now And I have the levels SPX and spy levels marked on my chart here This is my cloud notes column So here, for example, there's the 4000 spx 4000 key gamma strike the 39 98 combo four level And then this is showing spy levels and notice that Spy did breach the lower edge of the expected move for the week And this is something that's based on the options market And this is for the week. So this is the lower edge of the expected move for the week And now price is moving back above that level And you can see that, you know as well as in this chart that the SPX 39 74 and the spy 397 level were in play And then the spx 4000 level above Support and resistance And then finally, let's take a look at tesla So there's tesla strong drop in the morning. Let's go take a look at hero notice the Notice the weak hero signal here right here. This is the This is comparing the strength of the hero signal In the last 30 day range that's shown by the entire length of the slider and then the colored portion is the strength of the hero signal in the last five days so the Hero signal for tesla is weaker than it has been And as weak as it has been in the last 30 days and weaker than it has been in the last five days and up until You know, let's just say 1 32 o'clock. It has been generally trending down Let's just zoom in here so confirmed hero confirmed The short in the morning A little bit of a long I guess that's that's what I was looking at when I put that simulated call trade on and then trending down All right, let's go One thing other thing that I want to take a look at Is tesla and equity hub And this is looking at the key daily levels for the last 10 days And here I can see that there has been No increase or decrease in the key gamma strike And from yesterday to today A slight drop in the hedge wall And then the for the last oh six seven days the Call wall has dropped down so it dropped A couple of days ago Down from 220 down to 200 and then today the Put wall dropped from 190 To 180 So overall, I I take that as as bearish For for tesla. So this is doing further investigation. Let's say you were planning to trade Planning to trade tesla Today if you traded tesla every day, you might want to do some investigation here And you can see that traders are Not anticipating higher prices In fact looking and anticipating potentially lower prices with that put wall moving lower the hedge wall moving lower And again, no increase in the key gamma strike or the call wall and the slight slight shift lower in the call wall over the last few days And again, I would interpret that as bullish and just even though there's no change in the key gamma strike Further investigation shows that Some of these other levels were dropping So now let's go to book map and let's zoom actually i'm going to Zoom in this Like this And so there's the move down As hero is dropping Options traders were taking negative delta positions And then there's a clear target At the 180 put wall Oops Clear target here at the 180 put wall. Sorry about that Wrong tool Okay, the 180 put wall notice all the liquidity there and the absorption at that level Okay, so that's tesla multiple Notice it's all below vwap multiple short entries reversal at 184 Other short entries here down to the 180 180 put wall And if you were fast enough you could have caught that one as well Okay, let's let's just wrap it up here Let's go back Let's go to thinkorswim and take a look and see how our Long tesla call is doing And it looks like we have recovered a little bit So that's the advantage of just putting on a kind of a set it and forget it long Long call here not worrying it's defined risk. So now it looks like we are up 2750 So far for the day Still we're experiencing that that theta burn of Almost 98 dollars a day and one other thing that I was looking at today was Another way to trade zero dte looking especially at a A trading range for the day and I think I mentioned this a A butterfly so down at the 39 74 low You could say, all right, I think price is going to go back up to 4 000 today. So this is expiration 8 march And this is a butterfly. So this is just a simulated trade showing Paying 25 cents for that. So you're paying 25 dollars To to potentially make you you're certainly never going to make 400 dollars on this but if you know, it's certainly possible to make a couple hundred dollars on this So this blue line is showing At expiration the purple line is showing right now So Right now this position is up Five dollars. So not enough to cost your cover your commissions spx is Quite expensive to trade So, you know, if you do this every day your broker is going to love you But it is, you know, if you catch a a big winner Every now and then, you know, you could Could do well with this this strategy and this is this is something that I would consider Very low risk high high potential reward. It's a low probability but notice how a The this curve this profit and loss diagram bends for a butterfly And even though this is just a five wide Short the 4,000 Calls and then long the 39 30 39 95 and 4,000 calls. So this is a An expected move butterfly again asymmetrical reward to risk and you can make profit You know, you make a profit on this even if Price does not make it within the blue line Blue lines fast enough Okay, so You know, just another way of looking at this That's all I had for today and I want to thank you for your questions and comments And thanks for watching and I will see you tomorrow. Thanks again. Bye


The N-protein of three highly pathogenic coronaviruses, SARS-CoV, MERS-CoV and SARS-CoV-2, has been identified as a factor that contributes to the development of severe inflammation and lung damage during infection. The N-protein interacts with a key serine protease called MASB-2, which leads to increased complement activation and the accumulation of C4B, C3 and C5B, nine molecules on the surface of cells. This results in aggravated lung injury in mice and humans infected with the virus. Blocking the N-protein's interaction with MASB-2, depleting MASB-2 from the body or using drugs to reduce complement activity can all reduce the severity of lung damage caused by the virus. These findings suggest that targeting the N-protein, MASB-2 interaction could be a potential therapeutic strategy for treating severe coronavirus infections. This article was authored by Ting GAO, Lin Su, Hainan Liu and others. We are article.tv, links in the description below.


Back to sailor.org's computer skills and literacy course. You now have a handle on some of the basic terms and concepts surrounding computers and their use. You're well on your way towards increasing your computer literacy skills. You have now toured the inside of a computer and learned the difference between computer hardware and computer software. By learning how computers work and by taking a closer look at the inner workings of the computer, you can better understand why specific programs are used to accomplish certain tasks. While this technical information is highly useful, we think you'll also find the common computer terminology that you learned especially important in reinforcing your prior learning and introducing new terms to you. In this unit titled, The Internet and the World Wide Web, we will begin by asking the question, what is the internet?  You will also view a video that will introduce you to the system that makes up the World Wide Web and will explain various terms including browsers, code packets, servers and links. This video provides you with an easy to grasp presentation of all of these computer concepts and how they work together. The next subsection introduces you to communicating with people through the internet. Communicating with people online has become increasingly popular. This section focuses on how you can communicate with others using the World Wide Web. You will take a look at screenshots or still pictures of computer screens in order to visually learn how to use email. The email explanations provide you with detailed steps and explanations that will make you confident in creating an email account for yourself and beginning to send and receive messages. While accessing the internet and its resources is exciting, it is important to learn how to be safe online. You will therefore learn about internet threats and how you can protect yourself online and surf the internet safely. If you aren't familiar with the term surf the web, this is a popular phrase used to describe browsing the internet or accessing various web pages online. Note that the section on internet security is crucially important. Please read it carefully and take notes. If you follow the advice offered by experts in their fields in this unit, you will find that you will be better able to navigate the World Wide Web and perform a variety of functions. The next unit, Unit 3, computer security and troubleshooting will offer you even more in-depth information on security, privacy, and information on troubleshooting techniques. I'll see you when you reach Unit 3. For now, enjoy exploring the internet and the World Wide Web.