bitmap display

hardware A computer output device where each pixel

displayed on the monitor screen corresponds directly to one

or more bits in the computer's video memory. Such a

display can be updated extremely rapidly since changing a

pixel involves only a single processor write to memory

compared with a terminal or VDU connected via a serial

line where the speed of the serial line limits the speed at

which the display can be changed.

Most modern personal computers and workstations have

bitmap displays, allowing the efficient use of graphical userinterfaces, interactive graphics and a choice of on-screen

fonts. Some more expensive systems still delegate graphics

operations to dedicated hardware such as graphicsaccelerators.

The bitmap display might be traced back to the earliest days

of computing when the Manchester University Mark I(?)

computer, developed by F.C. Williams and T. Kilburn shortly

after the Second World War. This used a storage tube as its

working memory. Phosphor dots were used to store single

bits of data which could be read by the user and interpreted

as binary numbers.

[Is this history correct? Was it ever used to display

"graphics"? What was the resolution?]

(2002-05-15)