UNIX - A powerful operating system firstly developed by AT&T. This operating system is commonly used by big companies, as it is hardware independent and very reliable.

Unzip - To extract a Zip archive.

Upload - The process of sending data from a computer to a remote system, such as FTP server and/or the Internet.

URL - Acronym for Uniform Resource Locator.

USB (Universal Serial Bus) - A plug-and-play interface between a computer and add-on devices, such as keyboards, telephones, digital cameras, scanners, and printers. USB devices are very conveniently connected to a computer as you do not need to turn off or restart the computer, you can connect the USB while the computer is running.

USB Hub - A multiple-socket USB connecter, that allows many USB devices to be connected to one computer via a single USB port.

USB Pen Drive – Flash memory data storage device.

Virus - A manmade computer program that duplicates itself into the other programs stored in a computer causing a negative effect. It can destroy or corrupt data stored on the hard disk and even destroy the overall operation of a computer. There are different types of viruses:

Boot Viruses - Are stored in the boot sectors of a hard disk so when you start up the computer the virus is ready to “attack”.

File Viruses - Are stored in program files so when you run the infected application, the virus code attacks.

Trojan Horse - Is not exactly a virus but a program that contains malicious programs. It is disguised as something benevolent such as a screen saver or a game.

Worm - Is a self-replicating computer program that launches a software that destroy data stored on the hard disk. As opposed to a virus that must attach itself to an existing application, a worm uses a network to send copies of it to other computer terminals and it normally does so without the awareness of the users (by sending emails).

Warm Boot - Restarting a computer without first turning off the power.

Webcam - A real-time video camera that takes live images which can be accessed via the Internet.

Window - A visual area, normally rectangular, displaying a graphical interface that allows users to manipulate by pointing with a mouse. You can have many windows open simultaneously and therefore work on different applications in parallel. Microsoft named their famous software “Windows” after this graphical interface.

Windows – An operating system with a graphical user interface developed by Microsoft.

Word Processor - A computer system or program for setting, editing, revising, correcting, storing, and printing text.

World Wide Web (“WWW” or “the Web”) - A network of servers on the Internet that use interlinked, hypertext databases and files. It was created in 1989 by a British computer scientist, and is the main platform of the Internet nowadays.