We take powerful computer graphics for granted nowadays, to the point where we complain when 4K games won't play at 60fps. But YouTube's showed how tough designers had it back in the 80s just to make color graphics work, period, on 16K machines of the day. They had to use a variety of workarounds just to get 16 colors on a 320 x 200 screen, as that would normally eat up your entire 16K of RAM right there. Developers for machines like the NES and Commodore 64 resorted to dividing the screen into "cells" that could each hold only two colors, a trick that used up just 9K of memory.

http://www.engadget.com/2015/08/19/8...raphics-video/