Hardware: Output

Introduction
This section deals with output hardware devices.

A users main interaction with a PC is via a device that enters data into a computer (input device), or displays that data as information (output device).

Visual Display Unit (VDU)
A device usually used for output to display the current status of programs and data files, but can be modified to accept light-pen input or touch.

Graphics adaptors
Connection to the PC's motherboard is via Graphics adaptor. This may be either integrated into the motherboard or as a separate circuit Board installed in one of the PC's expansion slots.
 * Standard Display Adapters ;
 * MDA Monochrome Display Adapter (80 x 24 characters), usually Green, Amber or White.
 * Hercules Mono - 720 x 348 pixels
 * CGA Colour Graphics Adapter 16 Colours - 640 x 200 pixels
 * EGA Enhanced Graphics Adapter 16 Colours - 640 x 350 pixels
 * VGA Video Graphics Array 256 Colours - 640 x 480 pixels
 * sVGA Video Graphics Array 256 Colours - 800 x 600 pixels
 * XGA eXtended Graphics Array - 1024 x 1024 pixels
 * Other (Video cards now allow for higher pixel densities to enable accurate display on large monitors).
 * Eg. 1280 x 1280, and beyond.


 * Colour depth
 * 8 bit = 256 colours
 * 24 bit (True colour) = 16 million (16,777,216)


 * Connectors
 * VGA
 * HDMI

Digital/Analog converter
A device that converts discrete numbers from a computer (digital) to physical measurements (analogue) to that are then relayed to device to perform or manage a process.