Jr. Pac-Man/Versions

Atari 2600
Developed by GCC in 1984, but not released by Atari until 1987. When the Tramiels took over Atari, they stopped several home console projects to concentrate on the home computer market. When the NES revived the home console market in the U.S., Atari rededicated themselves to the 2600 market and published this version of the game. Although the maze scrolls vertically instead of horizontally (presumably due to the fact that vertical scrolling was easier to accomplish on the hardware), this version is celebrated as the best official port of a Pac-Man game to the Atari 2600 by many players.

Atari 5200 & 400/800/XL/XE
Like the company's conversion of Super Pac-Man, developed by Atari in 1984 but never released. A pirated prototype of the ROM has been around almost since the game's cancellation. The leaked ROM was originally intended for the Atari 5200, but was later hacked in order to make it playable on the Atari series of home computers as well.

Commodore 64
Developed by Beam Software and released by Thunder Mountain in 1988. Interestingly, this version of the game does not scroll, which is a surprising fact given how capable the C64 is of scrolling. Then again, considering the graphics of the C64, if scrolling had been implemented it might have been used considerably less than in the arcade (due to the wider screen resolution) so the decision to remove the scrolling might have been deliberate, as opposed to a limitation.

IBM PC MS-DOS
Developed by Beam Software and released by Thunder Mountain in 1989. There is a separate CGA and EGA version (CGA version shown here). Apart from the colors, it is essentially identical to the Commodore 64 version.