QDOS (Quick and Dirty Operating System)
QDOS was a subset of CP/M, then Microsoft bought QDOS and made it MS-DOS. FOXTROT!
Microsoft Disc Operating System
MSDOS was officially released in 1981 by Microsoft.
No. Office 2007 requires Windows.
MicroSoft - Disk Operating System
Microsoft with Bill Gates he later left before MSDOS
PCDOS an IBM branded version of MSDOS, licensed to IBM. Eventually IBM abandoned it and MicroSoft took over direct marketing of MSDOS.
MS-DOS was based upon 86-DOS by Seatle Computer Works. When IBM developed their first PC, they approach Microsoft to write the operating system; at that time, Microsoft wrote computer applications and, in particular, languages - MSBASIC was the industry standard - and didn't have an operating system. Bill Gates realised the opportunity and bought the rights to 86-DOS which was renamed MS-DOS to supply for the IBM-PC.
There is no any software for MSDOS shell as MSDOS is itself a system software.
Start=>Run=>msdos
A disc operating System (DOS) which was marketed as MSDOS (MicroSoft Disc Operating System). It enabled the open platform, IBM Personal Computer, to be operated by typing in simple commands.
This is quite complicated; Microsoft developed PC-DOS for IBM in 1981 and shortly afterwards started selling MS-DOS - which was a different product - to other companies. However, as time passed "IBM PC Compatibility" became an important selling point and in 1987 MS-DOS and PC-DOS were essentially the same product.