It can be hard for modern players to realize just how brutal the memory constraints were on early computers such as the Commodore 64. The video embedded above does a great job of explaining the interesting ways developers worked within the confines of the system just to get colorful images on the screen.
Take, for instance, the nice piece of pixel art below.
Pretty good, right? There are lots of colors and it's easy to understand what you're looking at. It's a successful piece of art, but how do you put that on the screen without using up all your memory? Easy: break the screen into color cells, and only use two colors per cell.
The video goes into more detail, but this allowed for beautiful images that didn't eat up all your memory. It also had to be hell on the artists; the trick of creating such colorful images that only used two colors per cell couldn't have been easy, especially on detailed images like the one above.
In other words? Respect your elders.