| 100% | WINDOWSXP | 9 | Microsoft operating system that preceded Vista |
| 56% | WINDOWS | 7 | Microsoft operating system that came out in 1985 and now dominates the personal computer market |
| 55% | CPM | 3 | Operating system that preceded DOS, created in 1974 and used on Intel 8080/85-based microcomputers |
| 46% | VISTA | 5 | Operating system that succeeded Windows XP |
| 46% | DOS | 3 | Early Microsoft operating system |
| 45% | UNIX | 4 | Operating system that's an alternative to Windows |
| 45% | UNIX | 4 | Operating system that was developed at Bell Labs |
| 45% | UNIX | 4 | Operating system that succeeded TOPS-10 in usage |
| 44% | PIE | 3 | Operating system that a lot of Android devices run |
| 43% | GNU | 3 | Operating system that shares its name with an African mammal |
| 43% | YOSEMITE | 8 | Apple operating system that's also a geographical name |
| 42% | UBUNTU | 6 | Linux operating system that means "humanity" in certain African languages |
| 40% | BCS | 3 | N.C.A.A. ranking system that preceded the College Football Playoff |
| 38% | WINDOWS | 7 | Microsoft's PC operating system |
| 37% | CTA | 3 | Org. that operates the El train system |
| 37% | SEPTA | 5 | Org. that operates Philadelphia’s rail system |
| 35% | MSDOS | 5 | ___ Mobile (Microsoft operating system announced on April 1, 2015) |
| 32% | UNIX | 4 | Operating system since 1969 |
| 32% | DOS | 3 | Operating system for PCs |
| 31% | SPRINKLER | 9 | System that waters lawn |
| 31% | USENET | 6 | System that popularized ''FAQ'' |
| 31% | JOBROTATION | 11 | System that varies tasks* |
| 31% | OLFACTORY | 9 | System that controls smell |
| 31% | ANDROID | 7 | Operating system developed by Google |
| 31% | UNIX | 4 | Operating system analogous to Windows |
| 31% | UNIX | 4 | Operating system with many clones |
| 31% | UNIX | 4 | Operating system in many servers |
| 31% | UNIX | 4 | Operating system since the 1970s |
| 31% | UNIX | 4 | Operating system since the '70s |
| 31% | SOFTWARE | 8 | Operating system of a computer |