| htext | WebKNotes HTXT Document |
| htm | Hypertext Markup Language Document |
| htmhjt | Treepad v6 Text Database |
| html | Hypertext Markup Language Document |
| html5 | Hypertext Markup Language Document |
| htx | Extended HTML Template |
| htxt | WebKNotes HTXT Document |
| hu | Hungarian Language Info File |
| hus | Husqvarna Viking Embroidery Design |
| huv | Husqvarna Viking Designer Graphic Data |
| hvs | Cubicon Cubicreator G-Code |
| hw3 | World Literary Heritage Document |
| hwdt | Thinkfree Office NEO Word Template |
| hwp | Hangul Word Processor Document |
| hwpx | Hangul Word Processor 2010 Document |
| hwt | Hangul Word Processor Template |
| hxl | Microsoft Help 2 Registered Namespace List |
| hxn | Hexagon 3D Model |
| hxs | MS Help 2 Compiled Help |
| hyp | Adobe Acrobat Spelling Dictionary |
| Atari ST Guide Data |
| hype | Hype Document |
| hypetemplate | Hype Document Template |
| hyy | HiTi Photo Desiree v2 Template |
| hz | Chinese Hanzi Text File |
| i4d | Inform4 Document |
| iam | Autodesk Inventor Assembly Model |
| iba | Lectra Clothing Design Pieces Document |
| ibcd | InstantBingoCard Document |
| ic3d | IronCAD Compose 3D Scene |
| ical | iCalendar Data |
| icalendar | iCalendar Data |
| icd | IronCAD 3D Drawing Document |
| icdl | Internet Content Description Language |
| icdx | FilePic Document |
| icem | ICEM Surf Model |
| icm | ICEM Surf Model |
| icma | Adobe InCopy CS4 Assignment File |
| icml | Adobe InCopy Markup Language Document |
| icmt | Adobe InCopy CS4 Template |
| icp | Intercept Pantheon Schematic Data |
| ics | iCalendar Data |
| IronCAD Scene |
| icw | InterCAD Document |
| id4 | Infini-D Scene |
| idd | Adobe InDesign for Mac Document |
| ide | Autodesk Inventor iFeature File |
| idea | Adobe Ideas Document |
| idi | I-DEAS Document |
| ido | Infini-D 3D Object |
| idraw | iDraw Document |
| idrw | Claris Impact Drawing Document |
| ids | Infini-D Scene |
| idv | Autodesk Inventor Design View |
| idw | Autodesk Inventor Drawing |
| ifcxml | Industry Foundation Classes XML |
| ifd | InForm Document |
| ife | InfoFind Encrypted Document |
| ig2 | Catia IGES Document |
| ig4 | Image Systems Group 4 Fax Document |
| igds | Bentley MicroStation Design |
| iges | IGES Drawing |
| igf | Intercept Geometry File |
| igj | iGrafx Published Web Content |
| igp | Igor Engraver Published Music Notation |
| igr | SmartSketch Drawing |
| igs | IGES Drawing |
| igt | iGrafx Document Template |
| igx | iGrafx Document |
| igy | Microsoft Excel Web Query |
| ihf | IGOR Pro Help File |
| Inspiration Handheld Document |
| iif | Intuit QuickBooks Interchange File |
| ijpds | Scitex IJPDS File |
| iks | Microsoft InkSeine Document |
| ila | DATEV Document |
| ildoc | Interleaf Document |
| ilg | InstallShield Log |
| imm | iMindmap 4 Document |
| imp | Impatica Classic Document |
| Impression Document |
| Lotus Improv Spreadsheet |
| TEX-DESIGN Clothing Design Document |
| imr | Impromptu Report File |
| imtx | iMindMap Template File |
| imx | iMindMap 5 Exported Document |
| inca | Adobe InCopy CS3 Assignment File |
| incd | Adobe InCopy 2.0 Document |
| inct | Adobe InCopy CS3 Template |
| incx | Adobe InCopy Interchange Document |
| indb | Adobe InDesign Book |
| indl | Adobe InDesign Library |
| indn | Adobe InDesign for Mac Document |
| indt | Adobe InDesign Template |
| inf | Inspiration Mind Mapping Data |
| info | GNU Info Document |
| infopathxml | Microsoft InfoPath XML Form |
| inkml | Ink Markup Language File |
| inld | ImageNow Document Link |
| inm | Caere FaxMaster Fax |
