sentences:  Digital Research fought a long losing battle to promote CP/M-86 and its multi-tasking multi-user successors MP/M-86 and Concurrent CP/M-86, and eventually decided that they could not beat the Microsoft-IBM lead in application software availability, so they modified Concurrent CP/M-86 to allow it to run the same applications as MS-DOS and PC DOS.This was shown publicly in December 1983 and shipped in March 1984 as Concurrent DOS 3.1 (a.k.a.CDOS with BDOS 3.1) to hardware vendors.