<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)
Nearby terms:
bite « Bit Error Rate « bitmap « bitmap display » bitmap font » bitmapped display » bit mask
