The Lifehacker Tech Dictionary

Here at Lifehacker we talk about all sorts of tech-related things, and often times we'll use acronyms or terms that even the geekiest out there don't understand. So, we've created a tech dictionary to help you better read the internet as a whole, whether you're a tech noob or an advanced user.

This list by no means encompasses every technology term you'll run into, but it does cover the bulk of what we, and many other tech sites talk about frequently. It's meant as a quick resource to look up terms you run into, or to share with less tech savvy friends and family. It's broken down into six categories:

If you're looking for a particular term, use Ctrl+F to find what you're looking for on the page.


Hardware Terms

The Lifehacker Tech Dictionary

Arduino: An Arduino is a open-source piece of hardware typically used to prototype DIY projects. It also comes with free software to write your own code. Our guide to getting started with Arduino is a good place to start if you're interested in learning the basics.

CPU (Central Processing Unit): The CPU is the small piece of hardware inside your PC that carries out the instructions your software sends to it. It's essentially the "brain" of your PC. The better it is, the faster it can perform tasks (and the more it can perform at once). If you're building your own PC, check out our guide for more information on finding the perfect CPU.

Display Resolution: Display resolution refers to the number of pixels on your screen. It is usually shown as [width] x [height]. The higher the resolution, the more pixels your display can show. This means sharper, clearer images. On most computers, it also means more "space" for your desktop and applications. In some cases, higher resolution can increase your productivity (to a point).

Hackintosh: A Hackintosh is a computer you build yourself that doesn't use Apple hardware, but that runs Mac OS X. It's usually cheaper than buying a Mac, and our guide makes it very simple.

Microcontroller: A microcontroller is a small computer that includes everything you need (CPU, memory, etc) on a single circuit. They're typically used to complete one single process (like calculators, toys, remotes, appliances), and are popular with DIYers for creating everything ranging from a self watering garden system to your own clapper.

NFC (Near Field Communication): NFC is used for close range wireless communication. NFC can be used for a bunch of different things, but it has become most popular for quick sharing between smartphones—like Android Beam, which lets you share playlists and more just by touching your phone to someone else's.

Overclocking: Overclocking is when you run your CPU at a faster speed than it was intended. This means faster video editing, better gaming, and other benefits. Under the right conditions, most CPUs can run a little faster than their advertised rate, and if you want to do it yourself our beginner's guide to overclocking will help you get started. That said, overclocking can void a warranty on your CPU and there's always a risk you'll damage your processor.

PPI (Pixels Per Inch) : PPI is a measurement of how many pixels are in an image. It's often used to describe computer displays, tablet displays, and digital camera images. Essentially, the higher the PPI, the clearer the image is—like the iPhone's retina display.

RAM (Random Access Memory): RAM (also referred to simply as memory) is a temporary place for your computer to store information while the CPU does its work. Nothing is ever stored in RAM permanently. The more RAM you have, the better your computer is at multitasking, meaning you can run more programs at once and switch between them faster. RAM upgrades are cheap and very easy to do yourself, but make sure it's really worth it before you drop the cash.

Refurbished: When a piece of hardware—whether it be a laptop, smartphone or other part—has been refurbished, it means that part has been returned to the manufacturer, fixed up, and resold at a lower price. Sometimes the original unit was defective, but an item that's returned is often automatically considered refurbished even if it was never used. Buying refurbished electronics can save you a lot of money, but make sure you choose one from a reputable source with a good warranty.

RFID (Radio-frequency Identification): RFID is a wireless system used to track objects using tags. These tags include a small antenna that responds to radio waves. You'll often find these in clothing to prevent theft at retail stores, in toll booths to register a payment when you drive through, and even on credit cards so you can wave your card over a reader instead of swiping it.

SSD (Solid State Drive): SSD is a hard drive that doesn't have moving components. Because of this, SSD drives are much, much faster than typical hard drives and they're less susceptible to failure because they have no moving parts. SSD's are useful for anyone looking for a speed upgrade for application launching or boot time, provided you're not worried about storage space.

UPnP (Universal Plug and Play) : UPnP is a feature that allows devices on your home network to discover each other and access data or services. These days, it's often used for streaming media across devices on a network without a bunch of complicated set up procedures.

USB (Universal Serial Bus): USB is a cable or connector that allows your computer to communicate with other devices like a mouse or keyboard. They're also found in smartphones, game consoles, portable hard drives, and elsewhere. There are several different types and sizes currently on the market. Photo by DijutalTim.

Internet Terms

The Lifehacker Tech Dictionary

BitTorrent: BitTorrent is a protocol for sharing files between different users online. Unlike regular downloads, it allows you to download a single file or group of files from multiple people at once, making the transfer very fast and efficient. It's often cited as a means for piracy, but it's also used to distribute files without weighing down a server (Linux is often traded this way, for example). However, because of its relation with copyright, many internet service providers slow your internet connection if you're using BitTorrent, but you can anonymize your traffic to keep it from happening.

HTTP/S (Hypertext Transfer Protocol): HTTP is the set of rules that determines how files are transferred on the World Wide Web. Essentially, it's the foundation for the way the web works. HTTPS (HTTP Secure) is the same basic thing as HTTP, but with added security for sites like banks or online shops. HTTPS is incredibly important for keeping your data secure online.

Magnet Links: A magnet link is used on BitTorrent sites to start downloads without you needing to download a .torrent file first. Basically, it's a faster, easier way to start torrent downloads. Here's how to make use of them.

Net Neutrality: As the name implies, net neutrality is about making the internet a free and open platform that everyone gets equal access to. It's a pretty complicated, but important idea that affects how we all use the internet. The main goal of net neutrality is that every web site (whether it's Google, Bing, Amazon, or anyone else) should be treated the same when it comes to access speed.

OAuth: OAuth is an open protocol that allows you to secure your data by only allowing applications to access a limited amount of information. OAuth is what you use to log into other services using your Google, Twitter, or Facebook Account. If a smaller service get hacked, OAuth makes it easier to protect your information.

PHP (Hypertext Preprocessor): PHP is an open source scripting language used on most servers. It allows for web sites to create content that changes frequently (like Wiki's, blogs, etc). PHP is code that happens on the server side, and you see it when you fill out password forms, forums, and plenty more.

POP (Post Office Protocol)/IMAP (Internet Message Access Protocol): POP and IMAP are both methods for accessing your email on a desktop client like Outlook, or the mail client on your smartphone. POP pulls your email to your phone and manages it separately than on the server (say, Gmail). IMAP keeps everything in sync, so if you delete a message on your phone, for example, it'll be deleted in Gmail as well. In general, we recommend using IMAP for all your email needs, since it's less confusing.

RSS (Rich Site Summary): RSS is a service provided by blogs and web sites that creates a feed of always updating information from the site. RSS readers (like Google Reader) collect that information from various sites to create a news stream. Those feeds can be read online, or with a desktop or mobile app. Basically, RSS helps you keep up with all your favorite blogs and sites from one unified place.

SEO (Search Engine Optimization): SEO is the process of pushing a web site up on search engine results so that it's seen by a wider amount of people.

Usenet/Newsgroup: Usenet was originally a bulletin board service, but has since expanded into a place where people share files with one another. The files exist on a newsgroup, and can be downloaded with a Usenet service and client. Getting started with Usenet is incredibly easy, and it's arguably a safer means to transfer files than BitTorrent. Image remixed from Kati Neudert (Shutterstock).

Network Terms

The Lifehacker Tech Dictionary

802.11a/b/g/n: 802.11 is a set of standards for wireless local area networks that regulates how your computer communicates with your wireless router. Each of the letters (a/b/g/n) denotes different speeds and ranges, with Wireless N being the fastest. If you're not sure what you have check out our guide to knowing your network.

Ad Hoc Network: An ad hoc network is a wireless network that allows two devices to communicate directly with each other without the need for external equipment. It's useful for privately sharing files between computers as well as for multiplayer gaming.

Bandwidth: Bandwidth is the amount of data that can be transferred at once over a network, often between your computer and your internet provider, in a certain amount of time (e.g. 20 Megabits per second). In recent years, internet providers have put bandwidth caps on how much data you can transfer between your computer and the web, but it's easy to track how much you're using.

DHCP (Dynamic Host Configuration Protocol): DHCP is what assigns an IP addresses to each device on your network, and makes sure that no two computers have the same address (which would cause problems). It's how most computers receive their IP addresses on a network, although you can create a static one with your own computer or reserve addresses for a specific machine. That way, your devices always have the same addresses, which is useful for streaming video and other purposes).

DNS (Domain Name Service): DNS is a database system that translates a server or computer name from a numerical IP address into an easier to remember name (i.e. instead of 407.562.326.28). Every internet service provider has their own DNS system, but you can use different ones for better speed and security.

FTP (File transfer protocol): FTP is a system used to transfer data between computers on a network. FTP can transfer files between computers on a local network, or to transfer files online.

IP Address (Internet Protocol Address): An IP address is what makes it possible for computers to connect to each other. Every device that connects to the internet is assigned a unique IP address. You internet service provider assigns you either a static IP address that remains the same, or a dynamic IP address, which changes every time you log on. That said, you can fake your IP address with a proxy server, which is handy for remaining anonymous online.

ISP (Internet Service Provider): Your ISP is the company (Comcast, Time Warner, CenturyLink, etc.) from whom you receive internet access.

LAN (Local Area Network) : A LAN is the network that connects computers in a limited area, like your home. This is a closed system that outside networks do not have access to unless you let them in (say, by giving them a password).

MAC Address (Media Access Control Address): Your MAC Address is a unique number attached your hardware that identifies it to a network—like an ID card for your hardware. Your MAC address never changes, but you can spoof it to get around restrictions like coffee shop time limits.

NAS (Network Attached Storage): A NAS is a device (like a small computer or hard drive) that stores files that anyone on the network can access. Any computer on your network can access those files from anywhere in the house. It's easy to turn an old computer into a NAS you can use as a networked backup, media streaming, or torrenting machine.

NAT (Network Address Translation): NAT is what translates a web site on the internet to your local network so you can interact with the internet and vice versa. It also makes it so hundreds (or several) computers on a single network can all access the internet through one router without causing confusion.

Proxy Server: A proxy server stands between you and the internet to relay information. Think of it like a game of telephone where you're yelling to someone across the street who's then yelling the same thing across the block. A proxy server has two main purposes: to improve internet speeds by providing recently visited web sites on a local hard drive, and to filter the content you can access. When you use a proxy server, you can fake the internet into thinking you're somewhere you're not, which can enable you to watch region specific content incredibly easily.

SSH (Secure Shell): SSH is used to connect a computer (or other internet connected device) to another computer over a network the internet. It's commonly used to control your computer from afar, but also comes in handy when connecting an Android or iOS device to your computer.

Tethering: Tethering is when you use the internet connection on one device (typically your phone) for another device (typically your computer). This allows you to get internet access on your computer from virtually anywhere, even if you don't have Wi-Fi. Check out our picks for the best tethering apps on Android and the iPhone to try it out.

TLS (Transport Layer Security): TLS and it's predecessor, SSL (Secure Socket Layer) connect your computer to a secure server on the internet. TLS encrypts and protects the data you're sending, which is why it's commonly used for email, IM, banking, and online shopping.

VoIP (Voice Over Internet Protocol): Like the name suggests, VoIP is the system that allows live voice communications like you find on Skype or Google Voice to happen over the internet.

VPN (Virtual Private Network): A VPN is a group of computers networked together over a public network—usually the internet. A VPN encrypts what you're doing online so your data is always secure. It's a good idea to start using one if you're privacy minded or a security advocate.

WAN (Wide Area Network): A WAN is a large network that connects several smaller local networks (LANs). A WAN might refer to something as small as a corporation's network, or as large as the internet itself.

WEP (Wired Equivalent Privacy)/WPA (Wi-Fi Protected Access): Both WEP and WPA are security encryption for your home network. They're both meant to protect your home network from outside hackers, but it turns out both WEP and WPA are easy to hack into. WPA, however, is much more secure than WEP, so you should use it whenever possible.

Media Terms

The Lifehacker Tech Dictionary

Bitrate: Generally, bitrate refers to the number of bits—the amount of data—that are processed over time. We often see bitrate in reference to music files. For instance, the music you download from iTunes is 256 kilobits per second, meaning 256 kilobits of data is stored in every second of the song. See our explanation on bitrate for more information on how it can affect your music's sound quality.

Codec: A codec is a computer program that encodes or decodes video so it can be played. Essentially, a codec shrinks large movie files to make them playable on your device. Nowadays, so many different types of video formats exist that many people use a codec pack or specific program that contains multiple codecs and can play nearly anything.

DRM (Digital Rights Management): DRM is a technology that limits the use of media after its sold. Most often, it locks the media to your personal account so you can't share it with anyone, or use it on any other programs. It's often attached to books, videos, and games as a means to cut down on privacy. Because it's so restrictive, it's often an annoyance, but you can strip DRM away from books and videos pretty easily.

Lossless: Lossless refers to video or music that hasn't been altered from the original version. If you rip a CD or DVD losslessly, the file on your computer is the exact same in both bitrate, size, and quality as the original.

Lossy: Lossy is when you compress a media file so it doesn't take up as much space. This is what an MP3 or AAC file is. When you do this, you're deleting chunks of data, and thus losing some clarity or quality in exchange for space savings.

Media Center (also known as an HTPC or Home Theater PC): As the name suggests, a media center is a computer used exclusively for media. In most cases, this computer is attached to a television locally or over a network so you always have access to your shows, movies, music, and games on its hard drive. Common programs for media centers include the streaming-focused Plex and the extremely customizable XBMC. You can set up a media center that does everything for $500 or a more minimalist one for $35. It might sound complicated, but you can set it up for non-geeks very easily, and any annoyances you come across are easily fixed.

Streaming: Streaming is when media content is sent to you at the same time you're watching it. You do not download anything, and instead the content is stored temporarily while you listen or watch it. This is very common in music and video. In fact, it's how you watch videos on YouTube or Netflix—you don't download the file, you just start watching.

Security and Privacy Terms

The Lifehacker Tech Dictionary

Cookies: A cookie is a small bit of text stored in your browser that saves data from websites you visit. In some cases, these cookies are used to track the web sites you visit.

"Do Not Track": Do Not Track is a web browser setting and policy proposal that ensures your browsing isn't tracked by advertisers, social networks, or other web sites. However, it's currently just a suggestion your browser makes and not a rule because web sites do not have to obey the request.

Firewall: A firewall is either software or hardware to secure a computer or a network. It controls the traffic going in and out so that unapproved files don't slip in. A firewall is very simple to turn on (or off) on your home computer.

Phishing: Phishing is usually an email or web site you're directed to that attempts to trick you into giving information such as usernames or passwords by pretending to be a trustworthy site. In most cases, a phishing scam is easy to detect as long as you know what you're looking for.

Privacy Policy: A privacy policy is a legal document that tells you the ways a company can use, gather, disclose, or manage your data.

Sandboxing: Sandboxing is a security measure used by operating systems and programs that restricts software from accessing files they're not supposed to. You or your computer may sandbox a program if you aren't sure it's safe.

Terms of Service/Use: A Terms of Service (also known as Terms of Use) is a legal document that describes how you can use a service, piece of software, or web site. They often include stipulations about community behavior, marketing policies, and copyright. While they're often very long, it's possible to at least skim them quickly for certain keywords that may indicate you're signing up for something you're not comfortable with.

Software Terms

The Lifehacker Tech Dictionary

App Launcher: An app launcher is a program that quickly launches applications with a keystoke, but they can also do so much more. The point of an app launcher is to give you quick access to your most commonly used apps and actions.

Boot Disc/Live CD: A boot disc or live CD boots into an operating system without ever actually installing the operating system. Boot discs are commonly used to launch utility programs that troubleshoot software issues or install a new operating system. Live CDs are common with Linux because you can launch into an operating system without installing it, but they can also be used for getting rid of viruses and running a totally private and secure operating system on any computer.

Cloud Storage: Cloud storage is a type of service that allows you to store and back up your files to so they're not located solely on your hard drive. This makes them accessible from any computer, and keeps them backed up in case your hard drive dies. Dropbox or Google Drive are two popular versions of this, but you can make your own pretty easily.

Dual Booting: Dual booting is the ability to install and boot into two different operating systems on one computer. It's incredibly handy when you want to test out an operating system before committing to it, like with Windows 7 and Windows 8, or if you need to run programs from a different operating system from time to time, like with Windows and Linux, Mac OS and Linux, or even Mac, Windows, and Linux.

GUI (Graphic User Interface): The GUI is essentially what you see and interact with in your operating systems and programs. The GUI includes everything from the scroll bars to the button prompts. It's also one of our favorite things to hack and customize.

ISO Image: An ISO image is an exact duplicate of a physical disc on your hard drive that uses the *.ISO file extension. For example, an ISO of a DVD is identical to a DVD itself and your computer treats it the same way. It's an easy way to burn an exact copy of something, and you'll often encounter ISO images with boot discs or live CDs.

Jailbreak: Jailbreaking is the process that removes software limitations on Apple hardware like the iPhone, iPad, iPod Touch, and Apple TV. Once jailbroken, you have access to deeper parts of the operating system and you can run unapproved software. The jailbreaking process changes with each new version of iOS, but we have an always up-to-date guide to jailbreaking your phone to keep you on top of it.

Kernel: A kernel is the software that communicates between your hardware and your software. Essentially, a kernel makes it so your applications can communicate with your CPU, memory, and any other hardware devices.

Location-based: Location-based typically refers to the use of GPS to track your location and serve you specific information or perform certain functions. Location-based reminders apps like Checkmark for iOS or Geonote on Android are great for reminding yourself to do something when you're in a certain location. Location-based apps are also good for making your iPhone read your mind or turning your Android into a fully-automated superphone.

Push Notifications: Push notifications are the pop-up messages you get on your mobile device or computer from apps. These come in the form of email messages, Facebook notifications, or even to-do list reminders. We'd argue push notifications aren't as great as they seem, but you can make them much more useful with a little tweaking.

Rooting: Rooting gives you access to deeper parts of your Android's operating system. Much like jailbreaking on the iPhone, it allows you to do much more with the operating system itself, like add new features, overclock it to boost its speed, and more. Our always-up-to-date guide to rooting the most popular Android phones guides you through the process.

Text Expansion: Text expansion refers to a software utility that monitors what you type, and triggers a phrase when you type in a key combination. For example, you can use text expansion so when you type "omw" the program will replace that with "On my way." We love text expansion because when used properly it can save you hours of typing every day.

Title image remixed from Mariusz Gwizdon (Shutterstock).