Computer Terms Dictionary

 

A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z  

A        
Add-On: Add-On refers to a browser extension they are basically like a small program or feature addition to certain Browsers like Firefox or Opera you can get anything from Weather Updates to Extra Security, Internet Explorer also support extensions although they call them Browser Help Objects an example is the Adobe Acrobat Reader which allows PDF Files to be read in the browser window instead of having to download them.

Address: in computer terms this is generally referring to your email address or a web page address. Your home address is not an issue on the web.

Advanced Settings: A detailed set of rules which can be set or altered to a specified parameter by the user in programs or operating systems.

Application Software: Or simply application is a computer program that performs tasks that the user wishes to perform. It could be Microsoft word and you might use it to write a letter or Adobe Photoshop to edit a photo.

Apps: A shortened term for Application, An Application is a program e.g. Microsoft Office, Internet Explorer, Outlook Express etc.

Attachment: An Attachment is a computer file like an Image, Video or Document which can be included in an Email.

Animation: A simulation of movement created by displaying a series of pictures, or frames. All of these pictures put together can make a computer animated gif, which will be a moving picture. You can also animate writing, banners, and even entire websites. A cartoons on television is one example of an animation.

Antivirus Software: Is a type of Software Application used to identify and remove computer viruses, as well as other types of harmful files or software known as Malware.
Advanced Settings: Advanced Settings allow the configuration of detailed aspects of software or hardware, BIOS being the form of advanced settings for hardware and the Control Panel in Microsoft Windows could be considered advanced settings because most aspects of Windows like Appearance, Security and Network Connections can be changed there.

Autorun: Usually referring to removable media (Cd's and flash drives) is when the computer will ask you what you want to do when the computer detects these devices. For example if you insert a music CD it can be set to play when you insert it into the disc drive.  

AVI: Audio Video Interleave is a format for videos which can be played in many movie players, always check compatibility because an avi can contain different codecs.

B
Background: When speaking of a desktop, its the same as your wallpaper (seen below) but in any other instance it is an image, or set of images creating the area behind other things, so that you are not looking at a black screen all the time, it gives the screen more depth...
-Also known as the area that programs that work "in the background" go, which is nowhere

Backup: Backups are making a copy or copies of original data so it can be restored in case of data loss in case of a HDD failing or if files are damaged or corrupt.

Bios: Basic input output system. You can access this when you start-up a computer. It will say on the screen "To enter setup press .....key". It lets you change whether the CD-ROM or hard drive boots first. There are also settings to overclock some computer systems.
 
Bit Rate: This is a form of measurement for data transfer between computers or across the Internet e.g. Internet Service Providers detail there internet connection speeds in a Bit Rate form like 1mbps or 2mbps, also a note is that a Bit is different to a Byte, there are 8 bits in 1 Byte.

Blocked Senders List: A Blocked Senders List is a list of contacts or email addresses blocked from contacting you or interacting with you.

Bookmark: An internet bookmark saves the location of a webpage as a link, which can be catalogued and accessed easily at a later date. You can save bookmarks in your internet browser or on a webpage that stores bookmarks for you. In Internet Explorer bookmarks are called Favorites.

Boot: This is what an electronic device does when it first starts, it goes through a few steps before it allows you to use it, for instance your computer does a couple of very important things, it checks that all systems are running correctly, know as POSTinf, (Pre Operating System Test), then makes a list of all your devices to send to your operating system. Note that this is not all it does, just a quick summary.

Browser: There exist two main types of browsers, internet, and file system.
-An internet browser is a program which lets you access the internet in a comfortable way, most likely the program you are using now falls into this field.
-A file system browser is what you use to access folder and documents in your computer.

Browsing History: Browsing History is a log of your visited websites in your Internet Browser, when you visit a website like www.google.co.uk or www.google.com the website is logged in your history.

Bug: An error or glitch in programming and/or the code that makes it up.

C

Card: This is a general word, and so i will make the definition general as well
-A card for a laptop is an addon card which allows more functionality to laptops
-A Card for a camera or similar device, normally SD cards, are used much like flash drives and can be used to save data or anything else
-Playing cards, used to play many kinds of table games
-Internal computer cards come in many different flavours, AGP, PCI, PCI-E and so on, used to add functionality to desktop PCs
-The list goes on...

Case Sensitive: A term used to describe if it is of importance to use upper or lower case letters. Passwords can be case sensitive. For example your password may be YKL9at but if you type ykl9at it will not work.

CD-ROM: Compact Disk - (Read Only Memory), a one time use CD, meaning that once its burned at the factory it can never be edited again.

CD-RW: Compact Disk (Re-Writable), a type of compact disk which can be erased and rewritten many times rather then the standard 1 use, must can not be burned more than once using a normal cd-r drive.

Compatibility Mode: This is a process in which a computers Operating System tries to copy the way an older processor, operating system or hardware platform works to allow older software to remain compatible with newer hardware or software.

Control Panel: Part of an Operating System which allows the user to change the settings of a Operating System like adding new accounts, setting time limits on when the computer shuts down, adding and removing software etc.

Copy: This is a command normally done by selecting a body of text or image and then pressing the right click button and selecting the option "Copy" which allows the user to copy the text or image to another document.

Cookie: A text information message that is stored on your computer when you visit a web page. When you return to the page the cookie is used to recognize you.

CRT: Cathode Ray Tube, a type of Display used in older TVs and computer monitors, these work much like the "cathode ray tube' experiment many people have done in chemistry before, firing particles into a film behind the screen to make a picture, uses a 'firing mechanism' inside which moves up and down, really fast, basically its a set of magnets that can be polarized by electricity. which aim the particles in the right direction.

Cursor:Your mouse pointer, looks normally like a small arrow, but can be an hourglass, a hand or anything else imaginable. When it turns into a flashing line, ready to write text, then this is a cursor.

Cut: This is a command normally done by selecting a body of text or image and then pressing the right click button and selecting the option "Copy" which allows the user to actually take the actual text or image out of the area to be moved to another area by Pasting. NB. Clicking on on "Edit", up the top, after selection, will also enable this.

D
Database: A Database is a structured collection of data that is stored on a computer or server, the most used model of database is a relational database.

Decryption: What you do when you Decrypt something. This could be removing a security password.

Default Search Provider: A default search provider is an automatic option which is set by a user as there preferred choice e.g. Google, Yahoo and Ask are well known Search Providers with most probably using Google as there default search provider.

Desktop: It is everything you see when you start your computer except the taskbar. Your desktop has the icons on it that are shortcuts to programs and folders.

Device driver: A piece of software, which tells the operating system how to use a particular device.

Disk Drive: A Disk Drive is a device for computer storage it normally stores the Operating System and other important files like images and documents by using a mechanical arm which records data to disks and also retrieves the data when requested as well.

DISK / DISC: Comparably, a Disc is where the data is stored using lasers, like a Cd drive, and a Disk is a magnetic drive, like a hard drive, by definition they are the same.

Domain: On a local network the Domain is a group of computers that is run by at least one server (domain server) so that a set of policies (computer rules telling the computer who is allowed to do what) is permeated (passed) throughout the whole network in a quick and easy fashion.

DPI: Dots Per Inch, used in monitor and TV descriptions, tells you how many pixels the monitor or TV displays per square inch

Drive Letter: A drive letter is an assigned alphabetical letter to a disk or logical drive, the reason for this is to allow an organised file system, there are drives which are automatically assigned certain letters like the old 3.5" Floppy Drive which is assigned the drive letter "A", the even older 5.25" Floppy Drive is assigned "B", the Hard Disk Drive which stores the Operating System is assigned "C" and CD/DVD and Blue Ray Drives are assigned "D" or if there are 2 "D" and "E" any other addition of hardware like a  USB Drive is given the next available letter.

DVD: Digital Video Disk, this is mainly used as the name implies, to store movies to watch in a player, similar looking to a CD (compact disk) is can hold over 5 times as much and can be used to store things other then video, such as files, note that a DVD can not be played in a CD player, but most Cd's can be played in most DVD player.

E
Edit: Edit or Editing is the modification of data like text, pictures, music or videos.

Edit: Meaning to alter, improve or change an original document, image, video, sound or any other digital file.

Email Signature: An email signature is a bit of personalized text (such as your contact information or a favourite quote) that is automatically inserted at the bottom of every message you send.

Email client: A software program that will download and upload your emails from your mail server. An email client lets you read, create emails, send, reply to, read, and manage all emails. These include Outlook Express, Thunderbird, Incredimail, Pegasus and many others.

Email Server: An email server is like a post office in the real world. It collects your email and delivers it to your chosen email client or post box. Same with sending an email. It gets taken to the email server to distribute to the appropriate address.

Encryption: A security mechanism that uses a password usually to 'scramble' the data in such a way that only the original password can decrypt it

Executable file: AKA .Exe an executable file is a file that when run, executes some sort of code or initiates and or runs a program

F
Favicon A favicon is most widely known as the icon that appears next to a bookmarked webpage in your bookmarks or *favorites* folder, thus the name of *favorites*-icon. It can also be displayed in the address bar i your browser, next to the URL of the webpage.

Firewall: On the newer computers, Windows has added a basic 'Firewall'.  Firewalls are programs intended to protect ones computer from nasty things invading it while surfing/wandering through the internet, while running silently in the background.  Many feel the basic Firewall provided with Windows isn't sufficient and use an alternative one.  And if an alternative one is used, the basic Windows one must be turned off as two Firewalls conflict with each other.

Firewall: A little more advanced, this one is a program which blocks programs that the computer sees as a *potential* security hazard, it warns you that a program wants access out of your computer and asks you if you know what the program is trying to do, and if you trust it, if you don't know the program, or don't know what it does, you can research it using Google, the best web search site, and then make your decision, note that this also (helps to) prevent other people from getting into your computer from the outside.

File Permissions: File permissions are a set of rules or access rights to various types of documents, programs or areas and are applied to different user groups, the 2 user groups on a Windows Operating System are "Admin" and "Limited", Admin has all access rights and permissions on the computer, A Limited Account has less access rights and permissions hence the term Limited some examples of these missing permissions include installing programs, some programs may not run under limited accounts.

File: A File on a computer is either a document created by a program or it can be system files which make up an Operating System.

Folder: A Folder on a computer is used to store groups of files and other folders in an organised fashion, folders can be created by the user to make files easier to find similar to an alphabetised filing system in a cabinet or telephone directory.

Filters: Can refer to a couple of different aspects in computing, It can refer to an Email Filter which is used to process emails and organise it to specified criteria, the most general criteria is usually to delete or send suspected spam emails to a spam folder instead of your inbox. It can also refer to an Internet Filter which is used to restrict certain content or areas on websites to certain readers an example would be where Guests can't view profile details.

Floppy Disks: A form of old data storage, with the latest version being the 3.5" Floppy Disk which could hold anything up to 240MB but the most commonly used was the 1.44MB version, they were invented by IBM in the late 1960's but have been replaced by the newer CD, DVD, USB Stick and External Hard Drive which have the capacity to hold more information.
Format a hard drive: (Hard drive, re-writeable disks) To clear of all data. Clean to the original state of empty. A hard drive has to be formatted and partitioned to install an operating system.

Format text: It can also mean to format text by changing the font, color and size.

Forum: This is a member based website, usually free to join, where people gather to chat and converse on a particular subject. Forums usually focus on a niche subject and therefore are a great learning tool for everyone who participates.

G
Gamer: A Gamer refers to someone who plays video games either on a computer or console it could also include board games as well.

Gaming PC: A Gaming PC is a PC specifically built to play PC Games at higher frame rates, higher resolutions and higher detail than ordinary PC's, typically a Gaming PC will have a dedicated graphics card, quite a bit of RAM and a dual core processor at least.

Google: The number one search engine on the planet.

Graphics: Usually anything that is displayed by the computer is known as a graphic display (graph because it uses a pixel graph to place colors)

H
Hardware: The basic parts that make up your computer.

Hibernate: This is a feature in an Operating System where what is currently on the RAM is written to a nonvolatile storage device like a Hard Drive before powering off the system, so when the system is turned back on the computer will restart in its previous state i.e. the state it was saved at when the hibernation option was set.

Home Page: A Home Page is a webpage or website which is set to load when a browser is opened or the home button is pressed in the browser

Hard Disk: A Hard Disk shortened from Hard Disk Drive is a nonvolatile form of data storage, nonvolatile meaning it saves the data even when the power is turned off.

Hyperlink: A Hyperlink or normally shortened to a link is a direct link to a website or webpage reference normally used when quoting something, to back up an argument or just to share a website with someone.

Hover: Hover is what you do when you leave your mouse pointer over an item for a certain amount of time

HTML: (Hyper Text Markup Language) Basic Language used to build web pages.

I
ISP: (Internet service provider) An ISP is the company that supplies your internet connection to you. It could be a local phone company or even a pay TV company. You internet service provider usually sends you a bill for your internet connection.

Indexing: Indexing is the collecting, organising and storage of data to allow for fast and accurate information retrieval examples of this are the Search Engines like Google, Yahoo and Ask as well as the Search Feature in Windows which is similar to that of Search Engines.

Images: Images are photographs of a person/s, object/s or a landscape and are generally 2 dimensional images but can also be 3 dimensional as well.

Import: Import in computing generally means the import of data from another source for example When running Microsoft Access you can import data from a Microsoft Word Document.

Icon: A small graphic symbol for an application, file or folder. There are icons that you can use to open applications on your desktop. There are also icons in your taskbar, control panel, and more..

J
Jamoola: A free website template that is a fully equipped content management system.

Java and Javascript: These are two entirely different languages, despite the name, they are both languages used for computer programming and or web scripting.

Junk Mail: Is the term for advertising mail or email spam which is the sending of bulk email i.e. sending an email to many addresses advertising something they can be real advertising which can get annoying or fake advertising which can trick people in to buying something they don't need and infecting there computer.

K
Keyboard: A peripheral (add on to a computer) which allows you to communicate with your computer and type words and letters.

Kbps: Kbps stands for Kilobits per second which is a measurement of data rate transfer, not to be confused with KBps which is Kilobytes per second, the difference being the capital K and B.

L
Language: Refers to a programming language used to create programs and express algorithms on a computer operating system, examples of these include C++, HTML, Java, Javascript and PHP.

Links: This is the shortened term for "Hyperlinks" which refers to a website or webpage reference to show information about something.

Log On: Log On refers to a user logging on or signing in to a computer system or website account, it is a form of security measure where the user is identified by a username and password, it is used so the user can obtain access to the system.

M
Media Devices: Media Devices are a general term for an electronic device which stores and plays Music, Photos or Videos, Media Devices are normally connected to a computer for Music, Photo and Video Files to be transferred to the device, although some media devices like an iPhone and other Smart Phones include Internet Access for an Application Store or Media Store which allows files to be transferred directly to the device.

Media Player: Can refer to a few things including a Media Device which stores and plays media files like Music and Videos (explained more above), and Media Player software which will organise, hold and play media files on a computer some of the main ones are Windows Media Player which is preloaded on Windows Systems and Quicktime Player which is preloaded on Mac OS Systems.

MP3: MP3 or MPEG 1 Audio Layer 3 is a digital audio encoding format which is the most common audio storage.

Modem: This is a device which modulates an analogue carrier signal to encode digital information and can demodulate a carrier signal as well to decode the information, so it allows for the transfer of digital data across phone lines where if the digital data was kept in its original format it could not be transferred across the phone lines.

Motherboard: The central circuit board that provides electrical connections so the other components of a computer can communicate with each other. It is the main part to a computer. Everything is connected to it.

N
Notification area: This is the area of a windows taskbar in the right bottom corner that displays important information, such as the time, the network connection icon, sound icon, etc. Balloon notifications will popup if there are any updates or problems.  

O
OS: OS is usually an abbreviation for Operating System. Your operating system could be Windows Xp, Windows Vista, Mac OSX, Linux, etc.

P
Peripherals: Peripherals are those pieces of hardware that you add on to your computer. For example a mouse, keyboard, modem, monitor, etc.

Paste: This Command is activated by pressing the right click Button on where you require the text or image that you have Copied or Cut else where and selecting Paste. NB. Clicking on on "Edit", up the top, after selection, will also enable this.

Path: A Path specifies a unique location of a file in a file system, the path points to a file by following a folder hierarchy for example "C:\Program Files" is the folder where all the information for your programs are held, the backslash "\" denotes the next folder so C: (Local Drive) was the first folder to locate and then the folder "Program Files".

Parental Controls: Parental Controls are options which can be set by a parent to monitor and limit what their child can view or do on the computer as well as limiting the time they can spend on it.

Passwords: A password is a word, set of characters which can include numbers, it is used as a security measure for users or people with email addresses or online accounts so access can't be gained, it is advised that a user always keeps their password secret.

playlist: a list of songs, usually favourites, that have been compiled by the user to listen to as a group. I have an eighties music playlist, a country music playlist, and a rocknroll playlist.

Plug and Play: It's the magic that allows one to add a new mouse, new printer etc to ones computer the easy way ... one literally 'plugs it in' and it 'plays/works'.  Always, always if possible, buy a new device that says 'Plug and Play' on the package - so much easier than connecting these things step by step.

Plug and Play: Plug and play is a technology that came in around windows 3.1, really old since we are at windows 7 in December (2009), which in simple terms allows you to plug hardware into a computer and lets the computer recognize it, back before 3.1 you had to go into the PC and tell it what the device was and all the settings it should have.

Phishing: Phishing is the criminal process of trying to gain sensitive information like a username, password or credit card details by acting like a trustworthy entity via emails, most phishing emails are targeted at users on the most popular websites like Facebook and MySpace but also as various online banks.

Pixel: This is the smallest item that makes up an image, they are the small dots or squares of colour that make up your screen.

Ports: Ports can refer to 2 different things in computing, In terms of hardware a port serves as an interface between computers or peripheral devices examples of hardware ports are USB, Ethernet and TV-Out or HDMI, In terms of software a port is used to transfer data between computers the most common ports being TCP and UDP Ports which are used when exchanging information between computer over the internet.

Privileges: Privileges are permissions to preform an action e.g. create a files, create folders, read certain files, delete files, access to a device etc.

Program: A Program is a piece of software which is a set of instructions for a computer, they are usually executable files once installed on a system.

Q
Quick Launch Toolbar: Located in the Windows task bar at the bottom of the screen, next to the start menu. It holds shortcut icons to open programs quickly so you don't have to go to the desktop everytime you want to open something.

R
RAM: RAM or Random Access Memory is a form of volatile data storage, it basically stores data on currently running programs i.e. Internet Explorer, Outlook Express and even the Operating System, it is called a form of volatile memory because once the power is turned off all data that is on it is lost.

Read Only: Read-Only can refer to 2 things Memory or Files, In terms of memory it is referring to memory that is read-only i.e. Programs or the Operating System which is stored on a Hard Disk Drive, they are made read-only so they can't be edited very easily and because it is important information for the program or Operating System to run. It can also refer to files or documents which are set as read-only by the author.

Readyboost: Readyboost is a feature in Windows Vista and the upcoming Windows 7, it works by using Flash Memory either on a USB Drive or many other types of compact flash and uses it as disk cache.

Registry: The registry is where Windows based operating systems store all major settings for your computer. This includes software serial numbers and passwords, email settings and accounts and a lot more information. It is essentially the main brain of a computer.

Resolution: Resolution refers to display or digital television and the measurement used is pixels e.g. some High Definition TVs have a resolution of 1920x1080 which means the TV has 1920 Horizontal Pixels and 1080 Vertical Pixels.

Roll Back: A term used to describe reversing changes on a computer, either by rolling back computer drivers if problems have occurred when installing the latest version of driver or rolling the operating system back to an earlier date.

Router: A Router is a networking device used to fulfil the tasks of routing and forwarding information, on the internet information is directed to different ports. A router is used to network computers so they can share files and an internet connection.

RSS: RSS or Really Simple Syndication is a group of Web feed formats used to publish frequently updated works like news headlines or blog entries.

Run Command: On a Windows System the Run Command is used to open an application or document if the file path is known.

S
Safe mode: When you computer is started in safe mode the computer loads only the files necessary to run the basic Windows services. It is the NO-frills version of Windows, which allows you to diagnose problems by process of elimination.

Scanner: A device that is plugged into a computer which optically scans printed text, handwriting, photos or other objects and then creates a digital image of the thing you have scanned which is then stored on the computer.


Screensaver: Your screensaver can be set to start after a selected amount of minutes the mouse hasn't been used.  Originally it was intended to stop 'burn out' of one's screen/monitor and although many feel it's not necessary with the new flat screen monitors, it's still nice to have. In Windows you can choose animated pictures or even photo slide shows as your screensaver.

Screensaver: A screensaver is mostly outdated, and is now only used for power conservation, if you have an older monitor, a CRT more than 3 years old, you need a screensaver, what it does? It prevents an image from being "burned" into the back of your screen from being displayed too long, the technology, seen below under "CRT", is a little more aggressive than LCD or dlp monitors, to burn an image into a CRT it has to be on for a long time, displaying the same image, i mean a long time, normally it will not happen overnight...

Scroll: Scroll is what you do when you take the bar on the right side of the screen and pull it torward the bottom, that is the scrollbar, you can also scroll by turning the mouse wheel (the wheel in between the left and right mouse buttons) on most mice that have them.

Shortcut: A small file or link found on the desktop of a operating system which when clicked or double clicked (depending on settings) loads up a program or application.

Sleep Mode: Is a low power mode for computers and other electronic devices, used to save power on devices especially on laptops and allows for the user to quickly load up their user profile on the computer next time they use it.

Spell Checker: A program/application that checks words for the correct spelling against a dictionary and if spelt incorrect is normally highlighted with a red line under the word, they are most commonly found built into word processing software like Microsoft Word or Open Office Writer as well as email clients and browsers.

Spreadsheet: A computer application that mirrors a paper worksheet, it is a group of cells formed into a grid of rows and columns each cell can contain a number or letter or even a formula from which it can work out what a group of cells add up to or which piece of data to pick out. It is used especially for recording financial information because of it's ease of use, only one cell has to be changed if needed or it is being updated and everything else will update alongside it if setup with formulas.


Start Menu: This is similar to looking at a menu in a restaurant and deciding what one would like to order - only in this case, it's a matter of choosing which program within one's computer that you would like to use.  It's found by clicking on the word 'Start' or the start icon in Vista which is located in the bottom left of your desktop.

Start Menu: The start menu is like a listing of all the programs you have installed on your PC, it allows you to access them from a neat and easy to manage window, so that you don't have to navigate to the programs folder each time you want to start a program

System Information: Is a list of your basic computer specification, the operating system on it and the name you set or someone else set the computer to, other software is available that gives a more detailed overview of the computer as well, examples are SIW (System Information for Windows) and Belarc Advisor.


T
Task Scheduler: A program that is included with Windows that allows you to run programs, send emails, and set reminders, by setting tasks for your computer.

Taskbar: This is the bar at the bottom of your screen that displays your currently running applications, like this web browser window.

Terabyte: A terabyte or TB is a form of measurement for digital information storage, 1 terabyte is equivalent to 1000 gigabytes or 1,000,000 megabytes.

U
UAC: A security feature introduced in Microsoft's Windows Vista operating system, used to give programs and applications on the operating system certain privileges until the user verifies the program can run, the main reason for this being to limit malware infection to a computer.

UNIVERSAL PLUG AND PLAY: Universal plug and play is a technology that allows computers to interact, before vista this service had many flaws and security vulnerabilities and was recommended to be shut off.

Upload: Is a term used to describe when a user or the computer is sending data to a specified server or other computer, some common forms of uploading include the uploading of a image to a site like Imageshack or Facebook or even the uploading of videos to sites like Youtube.

Upgrade: Is the upgrading of a product like an operating system or software to a newer version thus replacing the older version, meaning improvements are made over the old version in some cases.

URL: (Uniform Resource Locator) A URL is the address of a particular webpage or document on the internet. You can find the URL of a wepage by looking on the top bar of you internet browser. The most common URL starts with http://www. but others can start with ftbtp:, ftp:, and more..

USB: Short for Universal Serial Bus is a standard socket found on a computer used to connect varying peripherals and other devices, the most common devices being memory sticks, webcams and mice.

V
Virus: A man made file that infects a computer in order to sabotage its files. Now we have man made programs to combat this problem. Antivirus programs, spyware programs, internet security programs, malware programs, and the list goes on.

W
Webpage: A webpage is a single page that can be viewed on the internet. A webpage has it's own unique URL. It might be a webpage that is part of a group of webpages that forms a website.

Website: A website can be a group of webpages or only one, however it is located on the same domain with the it's unique domain name. For example Tips4pc.com has about 1000 webpages that make up the website. Their address all start with www.tips4pc.com/webpage.

Web Server: A computer that holds a web page and makes it available on the internet. Therefore when a webpage is requested through an internet browser the web server serves it to you..

Wallpaper: When one first boots/starts a computer and it's finished loading, the picture or image that filled the computer monitor/screen is a 'wallpaper'.  There are several choices that come with all new computers, but one can also download others or even use any photo or other image within one's computer to create a personal 'wallpaper'.

Wallpaper: This is the image that is displayed on your desktop background normally from the time your computer starts until it is shut down.

X

Y
Yahoo: Yahoo is an all around site, offering everything from an alternative search engine, to free email and many other services.

Z
Zip File: A file or package of files that has been compressed in Zip format. A zip file has .zip as a file extension and can be unpacked or decompressed with file archive programs such as Winzip, Winrar, 7zip and more..