| Type | Code | Type Name | Description | Origin | File Extensions/Mime-types |
| FFF | D | Test | Test | test | test |
| 100 | R | 1stsheet | 1st | | |
| 101 | R | Calcsprd | Calc spreadsheet | | |
| 102 | R | Perl | Perl script (Also A06) | | .pl |
| 103 | R | UniMode | VIDC regs and ModeVariables for !UniMode2 screen modes | !UniMode2 | |
| 107 | R | OreDBase | Oregan Database – Archivist Pro | | |
| 108 | R | DataVox | SysBeep sound file with internal chunk structure | | |
| 118 | R | Angband | Angband saved game file | | |
| 11A | R | Z-Code | Infocom game file (a Z-Code program from old 8/16-bit machines new games can be compiled using Inform and played with Zip 2000) | | [.z1 - .z8] |
| 11D | R | TAP | !Tapes !Z80Em compressed 1-bit sound for emulators | !Tapes, !Z80Em | .tap |
| 122 | R | Genetic | Genetic Algorithm data | !MakeCreat, !Path, !GAAsm, !ViewCreat, !GALoader | |
| 127 | R | MOPAC | | !RasMol | |
| 128 | R | MOL | | !RasMol | |
| 129 | R | Alchemy | | !RasMol | |
| 12A | R | PDB | | !RasMol | |
| 12B | R | RasMolSc | | !RasMol | |
| 138 | R | MapprMap | !Mapper_O 2D map with overlays | !Mapper | |
| 152 | R | PolyData | Polyhedron definitions for !PolyDraw, !PolyNet | !PolyDraw, !PolyNet | |
| 153 | R | Cabri | !Cabriolet (dynamic geometry) | !Cabriolet | .sna |
| 156 | R | PsiWord | Psion Series 5 | | |
| 157 | R | PsiSheet | Psion Series 5 | | |
| 158 | R | Psion | Psion Series 5 | | |
| 159 | R | PsiRecrd | Psion Series 5 | | |
| 15A | R | PsiOPL | Psion Series 5 | | |
| 15B | R | PsiData | Psion Series 5 | | |
| 15C | R | PsiAgnda | Psion Series 5 | | |
| 16D | R | Organizer | | !Organizer | |
| 187 | R | awk | awk scrip | | |
| 18C | R | Lua | lua script or compiled object file for !lua | !Lua | |
| 18D | R | TaskLua | lua script or compiled object file to run in a task window. | | |
| 1a1 | R | Locate | Holds search definitions and/or search results for the Locate file-finder. | | |
| 1B5 | R | DirSync | Used by DirSync | | |
| 1CA | R | CashBook | Filetype for the CashBook personal accounts package | | |
| 3E2 | R | VistTune | Vistamusic Tune | | |
| 695 | R | GIF | Graphics Interchange Format | !Translatr, ChangeFSI, FYEO2, ImageMaster, ProArtisan24, Spr_2_Gif, WebGif2 | .gif image/gif |
| 9F8 | R | HD_BackJ | | !HD_Backup | |
| A9E | R | ChartDrw | ChartDraw application | | |
| A9F | R | GraphDrw | GraphDraw application | | |
| AA0 | R | MultiPlt | MultiPlot application | | |
| AAA | R | RiscOS3 | (Acorn) | | |
| AC9 | R | VF | TeX virtual font [.vf] | | |
| ACA | R | LaTeX | LaTeX source (industry standard) | | .tex application/x-latex; occasonally .ltx .latex |
| AD8 | R | PsiMBM | Psion Series 5 | | |
| ADF | R | PDF | Portable Document Format (Adobe) | | .pdf application/pdf |
| AED | R | SheetMac | Schema configure | Schema | |
| AEE | R | SheetWS | Schema macro | Schema | |
| AEF | R | Sheet | | Schema | |
| AF0 | R | ARCWrite | ArcWriter | | |
| AF1 | R | Music | !Maestro music | !Maestro | |
| AF2 | R | PostTray | Econet mail in-tray | | |
| AF3 | R | PostBox | Econet mail postbox | | |
| AF4 | R | PostFile | Econet mail filed | | |
| AF5 | R | PostData | Econet mail setup | | |
| AF6 | R | SimTrace | ASim trace | | |
| AFF | R | DrawFile | | !Draw/Draw Plus | |
| B02 | R | Meta | MidiWorks Meta Event | MidiWorks | |
| B11 | R | TTXscrpt | Teletext+ script file | Teletext+ | |
| B12 | R | TTXpage | Teletext+ page | Teletext+ | |
| B22 | R | DFSImage | !ImageDFS Image filing system for 5.25" DFS Disc Images | !ImageDFS | |
| B30 | R | FuzzySheet | | | |
| B31 | R | FuzzySheet | | | |
| B3A | R | SpellFrq | Words which have been looked up in !Spellbank | !Spellbank | |
| B3B | R | SpellBnk | !Spellbank user dictionary | !Spellbank | |
| B4F | R | Alphabet | Picture Book 2 Alphabet | Picture Book 2 | |
| B50 | R | RGSCOpts | Choices for Picture Book 2 etc | Picture Book 2 | |
| B6A | R | Illusion | Illusions Disk Magazine | | |
| B6F | R | WTModule | Wacky-Talky module | | |
| B72 | R | Compo | | | |
| B78 | R | MIDIWrks | MidiWorks score | MidiWorks | |
| B7B | R | Life | MacroLife Life plane | | |
| B7C | R | LifeForm | MacroLife Lifeform | | |
| B8C | R | Split | Part of a multi-part file | | .spt |
| B95 | R | WimpBasic | WimpBasic design files | | |
| BA0 | R | Z80 | !Z80Em ZX Spectrum emulator snapshot | !Z80Em | .z80 |
| BA1 | R | SNA | !Z80Em ZX Spectrum emulator snapshot | !Z80Em | .sna |
| BB0 | R | BibleNts | | !HolyBible | |
| BC5 | R | ImpDoc | Impression single file document | Impression | |
| BD6 | R | Audiowrk | Sound sample (registered as "Soundwrk" why?) | | |
| C24 | R | Architech | | | |
| C35 | R | CorlDraw | Corel Draw | | |
| C46 | R | UnixTar | Unix tape archive | Tar, Spark, SparkFS,SparkPlug | .tar application/x-tar |
| C7B | R | PhoneNum | !Grapevine phone number database including terminal type & key definitions | !Grapevine | |
| C85 | R | JPEG | JPEG image, (industry standard) | ChangeFSI, FYEO2, ProArtisan24, RapidJPEG, SwiftJPEG, Translator | .jpg .jpeg image/jpeg |
| CA0 | R | Metafont | Metafont source | | .mf |
| CA1 | R | TFM | TeX font metrics | | .tfm |
| CA2 | R | GF | TeX font bitmaps (uncompressed) | | .gf |
| CA3 | R | PK | TeX font bitmaps (compressed) | | .pk |
| CB5 | R | STSample | !Tracker/!STracker SoundTracker sample | | |
| CB6 | R | STModule | Sound Tracker music sequence and samples | AMFTracker,(freeware); BASTracker,(freeware); Digital Symphony,(commercial); Harmony,(freeware); !JukeBox; Mplayer,(freeware); ProTrack,(freeware); ProTracker,(freeware); S/Tracker,(freeware); !Tracker | .mod |
| CD5 | R | Tabs | | | |
| CE5 | R | TeX | TeX source, (industry standard) | | .tex application/x-tex |
| D93 | R | DDF | Impression Document Description Format | | |
| F89 | R | GZip | Gzip, (GNU Zip) | | .gz application/x-gzip |
| F95 | R | Code | A parallel of Data | | |
| F9D | R | DiscCD | Acorn Access, (peer-to-peer networking) | | |
| F9E | R | DiscDP | Acorn Access | | |
| F9F | R | DiscD | Acorn Access | | |
| FB0 | R | Allocate | Allocate | | |
| FB2 | R | MovieFS | MovieFS, MSVideo for windows, Waveform, Quicktime for Windows | Animator PRO, MovieFS, CineWorks | [.avi video/x-msvideo, .wav, .mov video/quicktime, .fli, .flc] |
| FB4 | R | DiscR | Acorn Access | | |
| FB5 | R | NoDisc | Acorn Access | | |
| FBC | R | PBAbacus | PocketFS | | |
| FBD | R | PBWrite | PocketFS | | |
| FBE | R | PBCards | PocketFS | | |
| FC2 | R | AIFF | Audio IFF | | also used by {SGI} and professional audio packages [.aif .aiff .aifc audio/x-aiff] |
| FC9 | R | WiniUtil | | | |
| FD0 | R | PCConfig | PC Emulator configuration | | |
| FD3 | R | DDEDebug | DDE Debug file | | |
| FD4 | R | MIDI | Musical Instrument Digital Interface, (industry standard) | Rhaposdy, (commercial); !Inspiration, (commercial); MIDIWorks, (commercial); ESPSynth, (commercial); MelIDI, (commercial); ReMidi, (shareware); Timidity, (freeware) | .mid, .midi audio/x-midi |
| FD5 | R | RiscOS3 | RiscOS3 | | |
| FD7 | R | TaskObey | TaskObey | | |
| FDD | R | MasterUt | BBC Master utilities | | |
| FDE | R | VTSetup | TCP/IP | | |
| FDF | R | VTScript | TCP/IP | | |
| FE0 | R | Accessry | Arthur desktop accessory | | |
| FE1 | R | Makefile | DDE Make Makefile | | |
| FEA | R | Desktop | Desktop setup | | |
| FEB | R | Obey | CLI commands, (Obey) | | |
| FEC | R | Template | Window templates | | |
| FED | R | Palette | Desktop palette | | |
| FEE | R | NotePad | Arthur desktop notepad | | |
| FEF | R | Diary | Arthur desktop diary | | |
| FF0 | R | TIFF | Tagged Image File Format, (industry standard) | ChangeFSI,Tiffin, (freeware); Translator, (shareware) | .tif .tiff image/tiff |
| FF1 | R | RawData | Raw unprocessed data, eg terminal streams | | |
| FF2 | R | Config | 240 byte CMOS RAM configuration | | |
| FF3 | R | LaserJet | HP LaserJet print data | | |
| FF4 | R | Printout | Dot-matrix printout | | |
| FF5 | R | PoScript | PostScript | AiEps-Drw, (careware); GhostScript, (freeware); RiScript, (freeware) | .ps .eps application/postscript |
| FF6 | R | Font | Fancy anti-aliased font, 4bpp bitmap | | |
| FF7 | R | BBCFont | BBC font, (VDU code sequence) | | |
| FF8 | R | Absolute | Absolute ARM code, (loaded at &8000) | | |
| FF9 | R | Sprite | !Paint/!Translatr sprite or saved screen | | |
| FFA | R | Module | Relocatable code module | | |
| FFB | R | BASIC | Tokenised BASIC program | | .bas |
| FFC | R | Utility | Transient program | | |
| FFD | R | Data | Output data | | application/octet-stream |
| FFE | R | Command | CLI Commands, (Exec) | | |
| FFF | R | Text | ASCII text | ChangeTxt, (shareware); Edit; StrongEd, (shareware); Uemacs, (freeware); Zap, (freeware.) | .txt text/plain |