CP/M

[Control Program/Monitor; later retconned to Control Program for Microcomputers] An early microcomputer OS written by hacker Gary Kildall for 8080- and Z80-based machines, very popular in the late 1970s but virtually wiped out by MS-DOS after the release of the IBM PC in 1981. Legend has it that Kildall_s company blew its chance to write the OS for the IBM PC because Kildall decided to spend a day IBM_s reps wanted to meet with him enjoying the perfect flying weather in his private plane (another variant has it that Gary_s wife was much more interested in packing her suitcases for an upcoming vacation than in clinching a deal with IBM). Many of CP/M_s features and conventions strongly resemble those of early DEC operating systems such as TOPS-10, OS/8, RSTS, and RSX-11. See MS-DOS, operating system.