There were a series of graphics adapters that started with the IBM PC: MDA = Monochrome Display Adapter (text only) https://en.wikipedia.org/wiki/IBM_Monochrom

There were a series of graphics adapters that started with the IBM PC: MDA = Monochrome Display Adapter (text only) https://en.wikipedia.org/wiki/IBM_Monochrome_Display_Adapter https://en.wikipedia.org/wiki/IBM_Monochrome_Display_Adapter CGA = Color Graphics Adapter https://en.wikipedia.org/wiki/Color_Graphics_Adapter https://en.wikipedia.org/wiki/Color_Graphics_Adapter EGA = Enhanced Graphics Adapter https://en.wikipedia.org/wiki/Enhanced_Graphics_Adapter https://en.wikipedia.org/wiki/Enhanced_Graphics_Adapter VGA = Video Graphics Array https://en.wikipedia.org/wiki/Video_Graphics_Array https://en.wikipedia.org/wiki/Video_Graphics_Array With some others like the Hercules which was MDA upward-compatible and did graphics as well as text. They didn't really do any graphics "processing"; just displaying memory-mapped pixels in various formats. They were memory-mapped, and the MDA used a different memory block than the CGA/EGA/VGA, so you could have two separate monitors simultaneously, doing things lke running something like Turbo Debugger on the MDA text display.