's original goal was to write about and publish programs for all of the computers that used some version of the MOS Technology 6502 CPU.

It started out in 1979[2] with the PET, VIC-20, Atari 400/800, Apple II+, and some 6502-based computers which could be from kits, such as the Rockwell AIM 65, the KIM-1 by MOS Technology, and others from companies such as Ohio Scientific.

Later on, the 6502 platform focus was dropped and IBM PC compatibles, Atari ST, and Amiga were added to its line-up.

Machine language listings could be entered with a program provided in each issue called MLX (available for Apple II, Atari and Commodore hardware, and written in BASIC).

Early versions of MLX accepted input in decimal, but this was later changed to the more compact hexadecimal format.

It was noted particularly for software such as the multiplatform word processor SpeedScript, the spreadsheet SpeedCalc, and the game Laser Chess.

Editors of the magazine included Robert Lock, Richard Mansfield, Charles Brannon, and Tom R. Halfhill.

Noted columnists included Jim Butterfield, educator Fred D'Ignazio and science fiction author Orson Scott Card.

was out of publication for several months when it was sold to General Media, publishers at the time of Omni and Penthouse magazines, in May of that year.

Publications, Lock started another company, Signal Research, which was among the first to publish magazines and books about computer games.