it is possible to represent a picture on a computer by using a matrix of (coloured) dots - the resolution of bit-mapped pictures is limited by the numbers of dots used (this contrasts with Vector graphics - for example, the Paint application produces bit-mapped graphics whereas Draw produces vector graphics)

A method of generating images by representing a picture image as a matrix of dots or picture elements, such as in an optical disk system. Also called raster graphics. See also OPTICAL DISK (OD), PICTURE ELEMENT, SCANNING.

Objects (often scanned) that are made up of bits (pixels) or dots are called bit-mapped (also called raster images). The more common bit-mapped formats are TIF, PCX, GIF, and JPG.