| gsa | Microsoft Office Groove 2007 Archived Workspace |
| gsb | Grisbi Document |
| gsd | Graphtec ROBO Master Vector Graphics |
| Profibus Generic Station Description |
| gsh | GenStat Spreadsheet |
| gsheet | Google Drive Sheet |
| gslide | Google Slides Document |
| gslides | Google Drive Presentation |
| gsp | Silhouette Studio SD Card Document |
| Sketchpad Document |
| gst | Graphtec ROBO Master Template |
| gstencil | OmniGraffle Stencil |
| gstudio | Graphtec Studio Document |
| gsw | GraphShow Worksheet |
| gta | Microsoft Office Groove 2007 Archive |
| gtc | Graitec Exchange Format Document |
| gtcx | Graitec Exchange Format Document |
| gtemplate | OmniGraffle Template |
| gtp | Guitar Pro Tabulature |
| gtt | Guntrams Tabletweaving Thingy Pattern |
| gtx | GX Text Document |
| guide | Amigaguide Hypertext Document |
| gul | JungUm Global Document |
| gv | Graphviz DOT File |
| gvdesign | Gravit Designer Document |
| gwb | GenStat Book |
| Interwrite Presentation Document |
| gwk | GraphiCode PCB Job |
| gx | Geometry Expressions Document |
| gxd | General CADD Pro Drawing |
| han | Headline Studio Animation |
| hbk | Mathcad Handbook Document |
| hbl | Braille Sense Format File |
| hcdt | Thinkfree Office NEO Cell Template |
| hcdx | Hallmark Card Studio Document |
| hcr | Broderbund PrintMaster Half-fold Card Data |
| hdd | HotDisc Designer Document |
| hdm | Handheld Device Markup Language |
| hdml | Handheld Device Markup Language |
| hdrp | HDRtist Document |
| hdw | Harvard Graphics Drawing |
| heb | DEcomp 3D Scene |
| hed | HighEdit Document |
| hef | Efficient PIM v1 Data |
| help | Windows Help File |
| hf | RayShade HeightField Format |
| hfd | HotDocs Form Document |
| hft | HaftiX Cross-stitch Design |
| HotDocs Envoy-based Form Template |
| hgo | Home Group Overhead Document |
| hht | Help and Support Center HHT |
| IdeaMax Document |
| hhtml | Realmedia Adstream HTML |
| hhtx | IdeaMax Document |
| highland | Highland Document |
| hip | Houdini Scene |
| hipnc | Houdini Apprentice |
| hjt | Treepad v6 Database |
| hlp | Windows Help File |
| hlz | MultiEdit Packed Help File |
| hmk | Hallmark Card Studio Document |
| hmw | Homeword for DeskMate Document |
| hnc | NoteCenter Notes Document |
| hne | NoteCenter Encrypted Notes Document |
| hou | ARCHLine v4 Drawing |
| hp8 | HP NewWave Write Text |
| hpd | HotDocs PDF Document |
| hpl | HotDocs Answer Source |
| hpm | HP NewWave EMM Text |
| hpo | HippoDraw Canvas Document |
| hpp | Haluha Pearls Design |
| hppcl | Printer Command Language Document |
| hpt | HotDocs PDF-based Form Template |
| hpux | HP Unix related Readme Text |
| hrx | Herolab E.A.S.Y Document |
| hsdt | Hancom Office Hanshow Template |
| Thinkfree Office NEO Show Template |
| hsf | HOOPS Stream File |
| ht3 | Hypertext Markup Language Document |
| ht5 | Hypertext Markup Language Document |
