National Teaching and Learning Change ProgrammeInformation and Communication Technology:
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• validation
  The automatic checking of data during input, to identify any which is obviously wrong.
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• value
  The data assigned to a variable.
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• variable
  The identifier (or name) associated with a particular memory location used to store data. By using a name the programmer can store, retrieve and manipulate data without knowing what the data will be.
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• variable type
  Describes the kind of data held by a variable, e.g. numeric, date, string, etc.
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• variable-length record
  A record where the total size of it is not predetermined but is governed by the amount of data to be stored. This is useful where textual data is to be stored, which would leave a lot of wasted space in fixed-length records. However, fixed-length records are more easily processed.
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• vector graphics
  Vector graphics is a screen display method in which each line of a drawing is produced on the screen individually. A line can be drawn in any direction (although there is a minimum width of a line) and so the display is a more accurate presentation of the picture with no jagged edges. The resolution of vector graphics screens is usually very high. Vector graphics is an expensive technique to implement with the result that most displays use raster graphics.
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• vector graphics
  Vector graphics is a method of creating images where the instructions for drawing certain basic shapes, such as lines, rectangles, circles and so forth, are stored, rather than the picture itself. These basic shapes, or
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• Venn diagram
  A way of representing the relationships between sets in diagrammatic form, e.g. circles which overlap where some of the data is shared between two different sets.
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• verification
  The use of checks to make sure data is consistent and has not been corrupted. Verification confirms the integrity of data as it is copied between different parts of a computer system. Copying should not change the data and differences detected would mean an error in the transfer. Verification can take place both when data is entered at the human machine interface and when it is copied between other components within a computerised system (including from remote sensors or other computers).
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• version
  A particular edition of a software program. Most software will have a version number.
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• vertical scrolling text
  Animated text which moves up the screen.
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• video camera
  A camera used to take and store video images.
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• video capture card
  A specialised analogue-to-digital converter that reads video signals from a video tape or video camera, digitises them, and stores them in a computer.
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• video card
  A video card (or adapter) is the circuitry which generates the signals needed for a video output device to display computer data. The data may be text only or text and graphics. The circuits are contained on a circuit board which is installed in the computer with output via a cable to the display unit (the monitor).
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• video clip
  A short section of video played on a computer or similar device.
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• video conferencing
  The use of communication links to have meetings between people who are geographically separated, using audio and video.
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• video graphics array (VGA)
  The minimum standard for PC video display, initially 640x480 pixels with 16 colours.
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• video player
  A software program which plays multimedia files, e.g. video and audio.
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• video RAM (VRAM)
  A separate high-speed memory into which the processor writes the screen data, which is then read to the screen for display. This avoids the use of any main memory to hold screen data.
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• view
  A menu option in most Windows programs, to change how the data is displayed.