| exsd | Eclipse Extension Point Schema |
| ext | Visual Studio .NET DB Project Extended Properties |
| exu | Euphoria Source Code |
| exv | Adobe Extension Script |
| exw | Euphoria Source Code |
| ey | Engine Yard Project Configuration |
| eze | ErZorScript Source Code |
| ezg | EZGraphs Source Code |
| f | Forth Source Code |
| f | Fortran Source Code |
| f4 | Fortran IV Source Code |
| f40 | PDP-10 Fortran-4 Source Code |
| f77 | Fortran Source Code |
| f90 | Fortran Source Code |
| f95 | Fortran 95 Source Code |
| facefx | FaceFX Actor File |
| facefx_ingame | FaceFX In-Game Actor Data |
| faces | FacesServlet Page |
| factor | Factor Source Code |
| fal | Falcon Script |
| fam | Falcon Compiled Module |
| fasl | Lisp Source Code |
| fb | Gforth Blocks File |
| fbap | FinalBuilder Action Package |
| fbl5 | FinalBuilder Project Log |
| fbl6 | FinalBuilder Project Log |
| fbp | wxFormBuilder Project |
| fbpinf | FinalBuilder Project Info |
| fbv | FinalBuilder Persistent Variables File |
| fcb | FAAST Builder File |
