The Silicon Disk System was the first commercially available RAM disk

RAM disk

A RAM disk or RAM drive is a block of RAM that a computer's software is treating as if the memory were a disk drive...

 for microcomputers.

It was written by Jerry Karlin in 1979/80. Karlin was joined by Peter Cheesewright and their company Microcosm Research Ltd marketed the product for a number of years. The product was available as a standalone and was also bundled with a number of different microcomputers and RAM-board products. The product was later sold by Microcosm Ltd

Microcosm Ltd

Microcosm Ltd is a UK company established in 1979. Its early claims to fame included Silicon Disk System in 1981 and Microcache in 1982 ....

. Initially, it was available for the CP/M operating system. Versions for the MP/M

MP/M

MP/M was a multi-user version of the CP/M operating system, created by Digital Research developer Tom Rolander in 1979. It allowed multiple users to connect to a single computer, each using a separate terminal....

, CP/M-86

CP/M-86

CP/M-86 was a version of the CP/M operating system that Digital Research made for the Intel 8086 and Intel 8088. The commands are those of CP/M-80. Executable files used the relocatable .CMD file format...

 and MP/M-86 operating systems followed. Following the launch of the IBM PC, a version for the MS-DOS

MS-DOS

MS-DOS is an operating system for x86-based personal computers. It was the most commonly used member of the DOS family of operating systems, and was the main operating system for IBM PC compatible personal computers during the 1980s to the mid 1990s, until it was gradually superseded by operating...

 and PC-DOS

PC-DOS

IBM PC DOS is a DOS system for the IBM Personal Computer and compatibles, manufactured and sold by IBM from the 1980s to the 2000s....

operating systems was produced.