Amiga is a family of personal computers produced by Commodore from 1985 until the company's bankruptcy in 1994, with production by others afterward. When introduced, it was one of a number of mid-1980s computers with 16-bit or 32-bit processors, 256 KB or more of RAM, and mouse-based GUIs. These include the Atari ST—the Amiga's primary competitor—Macintosh, Apple IIGS, and Archimedes. The Amiga differs from its contemporaries through custom hardware to accelerate graphics and sound, including sprites, a blitter, and four channels of sample-based audio. It runs a pre-emptive multitasking operating system called AmigaOS, with a desktop environment called Workbench.