System 9
# System 9

System 9 or System IX may refer to:

## Computing

* IBM System z9, the mainframe line
* Plan 9 from Bell Labs, the operating system
* Mac OS 9, latest release of Classic Mac OS operating system
* OS-9, the Unix-like real time operating system
* SYSTEM POWER 9, line of power supplies by be quiet!

## Other

* STS-9 (Space Transportation System-9), the Space Shuttle mission
