Many
video adapters support several different
modes of
resolution. All such modes are divided into two general categories:
character mode (also called
text mode) and
graphics mode. In character mode, the
display screen is treated as an
array of blocks, each of which can hold one
ASCII character. In graphics mode, the display screen is treated as an array of
pixels, with characters and other shapes formed by turning on combinations of pixels.
Of the two modes, character mode is much simpler. Programs that run in character mode generally run much faster than those that run in graphics mode, but they are limited in the variety of fonts and shapes they can display. Programs that run entirely in character mode are called character-based programs.
