U

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Undo

To reverse your last action. For example in Microsoft Word this is an undo arrow. You can also press the CTRL and Z key on the keyboard.

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UNIX

An operating system developed by AT&T that features excellent networking capabilities. It is not a popular operating system for the home user.

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Unzip

To unzip a zip file is to extract and decompress compressed files from it. If you are sent a zip file via email, you will need to unzip it before you can access the files inside it.

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Upgrade

An upgrade can be hardware or software that improves on the earlier version. For example you could upgrade Windows XP to Windows Vista or you can upgrade your hard drive be replacing a 40 GB with a 120 GB.

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Upload

To send something to the internet from your computer through your internet connection. You can upload files or webpage’s to a server or webhost, upload a video to Youtube, upload photos to my space, and the list goes on.

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UPS

Uninterruptible Power Source. If you have and UPS connected to your computer and the power shuts off, UPS will keep your computer running on battery backup until you shut it down correctly. This saves loss of data and information.

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URL

A URL (unique resource locator) or web address is the string of characters you type into a browser to access a particular website or other resource on the Internet. (eg. http://www.ourcommunity.com.au ).

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USB

Universal Serial Bus. A fast data transfer, serial interface, that allows multiple devices to be connected to your computer at the same time. USB also supports plug and play so it is easy to connect to your computer. Most digital cameras connect to the computer through USB.

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User

CReferring to a computer user. A user can have a username and password to login to a computer.

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User Interface

This is how a computer user interacts with a computer. There are two types of user interfaces, the command line interface (CLI) and the graphical user interface. An example of CLI is to type a command into the Windows Run box. An example of GUI is to perform a command by choosing a link on a menu in Windows or starting a program from the start menu.

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