| zw4 | EPLAN Project Backup |
| zw5 | EPLAN Project Backup |
| zw6 | EPLAN Parts Backup Data |
| zw7 | EPLAN Dictionaries Backup Data |
| zw8 | EPLAN Configuration Data Backup |
| zw9 | EPLAN Basic Project |
| zwb | Zamurai Mobile Whiteboard Data |
| zwdsp | eXtendable Wad Editor ZWDSP Data |
| zwe | MotionWorks IEC Express Project Archive |
| zwo | Zwift Cycling Workouts Data |
| zx | KGB ZX Spectrum Emulator Snapshot |
| zx82 | Speculator 97 Snapshot |
| zxb | ZX-Blockeditor Metafile |
| zxc | Components Engine Database |
| zxe | ZX-Editor Second Edition Format Data |
| zxl | Immersioni Dive Logbook Data |
| zxs | ZX Spectrum Emulator ZXS Snapshot |
| zxt | Warajevo Tape Image |
| zxu | Immersioni Dive Logbook DL7 Data |
| zyp | Reason Subtractor Synth Instrument Patch |
| zys | Business Integrator Database |
| zzd | ISIS Detailed Convergence Data |
| zzj | ISIS Outputs Matrix Coefficients Data |
| zzo | ISIS Control Unit Data |
| zzr | ZoneAlarm MailSafe Renamed File |
| zzs | ISIS Initial Conditions Data |
| zzs | MultiView Script |
| zzt | ISIS Unit Data Store |
| zzx | ISIS Results Data |
| zzz | WRAP Priority Sequence Stream Flow Availability Data |
