Thomas Alan Rolander is an American entrepreneur, engineer, and developer of the multitasking multiuser operating system MP/M created for microcomputers in 1979 while working as one of the first employees of Digital Research with Gary Kildall, the "father" of CP/M. CP/M and MP/M laid the groundwork to later Digital Research operating system families such as Concurrent CP/M, Concurrent DOS and Multiuser DOS. Wikipedia