Apple DOS 3.2 (included game)

The third major iteration of an operating system for the Apple II, this version began replacing Steve Wozniak's bundled Integer BASIC with AppleSoft BASIC, and with it, his BRICK OUT clone of Atari's arcade game Breakout (which he was responsible for implementing) with LITTLE BRICK OUT.

It plays according to a simple and long-established premise -- the player controls a paddle at the edge of the screen, moving so as to bounce a ball up into the playfield and knock gaps out of colourful walls. This particular version plays sideways (horizontally rather than vertically) and allows an unusual degree of user customization.