| NAC | Computer system security protocol, abbrev. |
| CAPTCHA | Captain and chief briefly advanced security protocol (7) |
| SSH | Internet security protocol |
| SCANNER | Computer input device that uses a light beam to scan codes, text, or graphic images directly into a computer or computer system. (7) |
| SOFTWARE | Instructions that tell a computer what to do. It comprises the entire set of programs, procedures, and routines associated with the operation of a computer system. (8) |
| UNIX | Computer system developed at AT and T |
| CIO | Corp. computer system overseer |
| REBOOT | Start again, as after a computer system crash |
| SKYNET | Evil computer system in 'The Terminator' |
| DOS | Computer system, initially (3) |
| WORDPROCESSOR | A computer system designed for word processing (4,9) |
| DESKTOP | Desmond, old soldier, needing work on computer system (7) |
| LOGOUT | Quit a computer system (3,3) |
| HACKER | Unauthorised computer system user |
| USENET | Early computer system of newsgroups |
| HACKING | Gaining unauthorised entry to a computer system (7) |
| ETHERNET | Computer system ___ enter somehow to secure article (8) |
| NET | The computer system, albeit full of holes (3) |
| TENET | Hard to leave the computer system in principle (5) |
| JANET | Plane carrying a new computer system (5) |
