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(colour look-up table, CLUT) A devicewhich converts the logical colour numbers stored in eachpixel of video memory into physical colours, normallyrepresented as RGB triplets, that can be displayed on themonitor. The palette is simply a block of fast RAM whichis addressed by the logical colour and whose output is splitinto the red, green and blue levels which drive the actualdisplay (e.g. CRT).The number of entries (logical colours) in the palette is thetotal number of colours which can appear on screensimultaneously. The width of each entry determines the numberof colours which the palette can be set to produce.A common example would be a palette of 256 colours(i.e. addressed by eight-bit pixel values) where each colourcan be chosen from a total of 16.7 million colours (i.e. eightbits output for each of red, green and blue).Changes to the palette affect the whole screen at once and canbe used to produce special effects which would be much slowerto produce by updating pixels.