| Version of the Microsoft OS operating system | |
| Working state | no longer supported as of May 1,1990 |
|---|---|
| Released to manufacturing |
January 19, 1973 |
| General availability |
January 21, 1973 |
| Marketing target | Personal computing |
| Succeeded by | Microsoft Venus |
| Support status | |
| ended | |
The Microsoft Operating System is a graphical operating system developed and released by Microsoft and the first version of Microsoft OS. It is considered to be the world's very first operating system.