In 1974, Dr. Gary A. Kildall, while working for Intel Corporation, created CP/M as the first operating system for the new microprocessor.  By 1977, CP/M had become the most popular operating system (OS) in the fledgling microcomputer (PC) industry.  The largest Digital Research licensee of CP/M was a small company which had started life as Traf-0-Data, and is now known as Microsoft.  In 1981, Microsoft paid Seattle Software Works for an unauthorized clone of CP/M, and Microsoft licensed this clone to IBM which marketed it as PC-DOS on the first IBM PC in 1981, and Microsoft marketed it to all other PC OEMs as MS-DOS.

In 1991, Gary Kildall and the other shareholders of Digital Research Inc., which Gary & Dorothy Kildall had founded in 1975, sold the closely-held private shares of Digital Research Inc. (DRI) to Novell, Inc., and then on July 23, 1996 all of the Digital Research, Inc. assets were acquired from Novell Inc. by Caldera Inc., a company founded by Bryan Sparks with the assistance of Ray Noorda, former Chairman/CEO of Novell Inc., and on July 24, 1996, Caldera Inc. filed a private Federal Antitrust Lawsuit against Microsoft Corp. for alleged illegal activities and unfair practices in the marketing of MS-DOS and its successors, including Windows 95 and Windows 98, both of which are still Digital Research CP/M at their essential core.  The lawsuit was settled out of court in January 2000 at which time Microsoft Corporation agreed to certain terms and paid certain funds to Caldera Inc.

In 2000, this CP/M Web site is official link site for CP/M resources worldwide.  Caldera Inc. owns all trademark and copyright to CP/M, whose successors are Caldera DR-DOS for single-user (client) purposes, and IMS Ltd. REAL/32 for multi-user and networking. Both are the most advanced versions of 32-bit DOS available, and are ideal for Thin Server and Thin Client Server solutions in the office, POS, embedded, communications, and other important emerging markets such as hard real-time for robotic control and full-fledged Video Computing.

CP/M Main Page

by John Elliott

Oak Repository - CP/M Archive

by Oakland University

 CP/M User's Group

Gaby Chaudry

by Don Kirkpatrick

Commodore and CP/M

by Herne Data Systems

Downloadable Z80 CP/M Compiler

by HI-TECH Software

Information & Texts About CP/M

by Gaby Chaudry

Switch from CP/M to DOS

by Bill Gates

The CP/M Story

by DangSoft

ZD Webopedia: CP/M

by ZDNet