What is the best way to animate sprites... without using keyboard characters?!

My friend along time ago use to use a XOR mask... each character was stored in afile... that looekd like

0 0 1 0 0
0 1 0 1 0
0 1 0 1 0
0 0 1 0 0

where each 1 would be the color that was read, and inputed with PSET.

Anyone hird of this method?