| Acronym | Meaning |
| SLEMU | SPacelab Engineering Model Unit |
| PALS | Photo Area And Location SYstem |
| TIFS | Total In-Flight Simulator |
| DFI | Development Flight Instrumentation |
| PORR | Preliminary Operat Ons Requirements Review |
| GSS | Ground Support System |
| NO | Nitric Oxide |
| BASS | Backup Avionics System Software |
| CDU | Coupling Display Unit |
| GPL | Goal Processing Language |