| htx | Microsoft Frontpage Database Results Data |
| hub | Lattice Reveal Analyzer HUB Data |
| hud | HUD Maker File |
| hud | SmartWare HUD Dictionary Data |
| huf | DtSearch Huffman Compression Table |
| huh | HydroCAD Unit Hydrograph Definitions |
| hun | Personal Paint Hungarian Language Data |
| hut | WaterGEMS Transient Analysis Output Log |
| hv | Microsoft Windows Mobile Hive |
| hvc | HotDocs Variable Collection File |
| hvd | HoverDesk Theme |
| hvd | Yamaha HV Voice Dictionary Data |
| hve | Microsoft Windows 8 AMCache Registry Hive |
| hvi | M3601A HVI Data |
| hvif | Haiku Vector Icon Format Data |
| hvs | Yamaha HV-Script |
| hvz | HoloViews Exported Data |
| hvz | hyperVIEW Simulation Data |
| hw | Marvelous Designer Hardware ID Data |
| hwas | eXtendable Wad Editor HWAS Data |
| hwdb | Linux Hardware Database |
| hwe | PLINK Hardy-Weinberg Exact Test Statistic Report |
| hwf | Hantek HDG2000B Wave Format Data |
| hwl | BrailleNote Apex License Key File |
| hwl | HttpWatch Watch Log |
| hwof | Microsoft Office for Mac Help Data |
| hwpml | Hangul Word Processor Markup Language Data |
| hwrx | Microvellum Hardware File |
| hwt | Huawei Phone Theme |
| hwv | Hades Waveform Viewer Data |
