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 user interfaces, interactive graphics and a choice of on-screen
fonts. Some more expensive systems still delegate graphics operations to dedicated hardware such as graphics accelerators.
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)