| File extension Name |
extension description |
| .H | ADS Include File (Autodesk, Inc.) |
| .H | Header |
| .H | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .H! | Flambeaux Tutorial Database |
| .H++ | C++ Header File |
| .H-- | Sphinx C-- Header File |
| .H0 | Magix Musstu File |
| .H1 | Magix Musstu File |
| .H1 | Bruker Aspect NMR Data File |
| .H16 | VC98 Include 16-bit File |
| .H19 | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .H2O | H2OMAP Water Master Project File (MWH Soft) |
| .H2O | Water Web Program File (Clear Methods, Inc.) |
| .H2O | Liquid Entertainment H2O Compressed Archive (Liquid Entertainment) |
| .H32 | BC45 32-bit Include File |
| .H3M | Game Map File |
| .H3R | H3R Panasonic Video Camera File (Panasonic Corporation of North America) |
| .H4C | Heroes of Might and Magic Map File |
| .H4R | Possible Container for .MP3 Files |
| .H4V | MPEG-4/AVC, H.264 Video File |
| .H5 | HDF5 Data File (The National Center for Supercomputing Applications) |
| .H5B | SuperHeat 5 Building File (Survey Design Associates Ltd.) |
| .H5R | WV-AS50A CD-R Video File (Panasonic Corporation of North America) |
| .H6C | SPP File |
| .HA | Compressed Archive |
| .HAD | MixlleniumEngine (Haydee) Web Server Module Style File |
| .HAF | HEAT Archive File |
| .HAI | NTgraph Nt09b-2b EMX Library File |
| .HAIRY | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HAK | BioWare Aurora Engine File (BioWare Corp.) |
| .HAK | GameHack File |
| .HAK | Neverwinter Nights File |
| .HAL | Mortyr Archive |
| .HAL | Hyper Access Lite OS/2 Data File |
| .HALOGEN | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HAM | Amiga Hold and Modify Image (Amiga, Inc.) |
| .HAM | Novell NetWare Disk Drivers NPA |
| .HAMMER | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HAN | Viewpoint Headline Studio |
| .HAND | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HANOI | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HAP | Hamarsoft HAP 3.x Compressed Archive |
| .HAPTAR | People Putty Haptek Character (Haptek, Inc.) |
| .HAR | e-Sword Harmony Resource (Rick Meyers) |
| .HARP | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HARPSAC | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HARPSAC2 | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HARRIER | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HASH | EnCase Forensic Drive Image Hash (Guidance Software, Inc.) |
| .HAT | HAT (HOORA Analysis Tool) Model |
| .HAT | Formula 1 Car Race 2001 Log Hat File |
| .HAV | Video Recorder Video File |
| .HAY | MixlleniumEngine (Haydee) Web Server Module Content File |
| .HAZ | Train Simulator Hazard File (Microsoft Corporation) |
| .HAZ | Flight Simulator Texture File (Microsoft Corporation) |
| .HBB | HAHTtalk Object File |
| .HBC | Home Buyers Calculator Suite |
| .HBC | HyperBac Compressed File (HyperBac Technologies, Inc.) |
| .HBC2 | HyperBac Compressed File (HyperBac Technologies, Inc.) |
| .HBE | HyperBac Compressed/Encrypted File (HyperBac Technologies, Inc.) |
| .HBI | Handy Backup Backup Index File (Novosoft LLC) |
| .HBK | Humanic Software Accounting Data |
| .HBK | MathCAD Handbook (Mathsoft Engineering & Education Inc.) |
| .HBK | Hex Workshop Hex Editor Bookmark File (BreakPoint Software, Inc.) |
| .HBK | HandyCafe Database File (Ates Software) |
| .HBK | Auto Backup Backup Archive (Han-soft Software) |
| .HBM | Hotline Book Mark (Hotsprings Inc.) |
| .HBX | Starmoney Macro file |
| .HBZ | Starmoney Macro file |
| .HC | BI/Suite Hypercube |
| .HC | High Resolution Cantone TIFF Bitmap |
| .HC | Header File |
| .HCA | Hammer Call Analyzer IP and TDM Network Traffic (Empirix Inc.) |
| .HCC | HydroCAD Stormwater Modeling System Storage Chamber Definition (HydroCAD Software Solutions LLC) |
| .HCD | C Poet Examples Advanced Inc File |
| .HCE | HydroCAD Stormwater Modeling System Hydrograph File (HydroCAD Software Solutions LLC) |
| .HCF | 123 Heading Creator Project File (Mark Hendricks and Hunteridge, Inc.) |
| .HCI | HydroCAD Stormwater Modeling System IDF File (HydroCAD Software Solutions LLC) |
| .HCL | Handwritten Claims Log |
| .HCM | IBM HCM Configuration |
| .HCOM | Macintosh Sound |
| .HCP | HydroCAD Stormwater Modeling System Project File (HydroCAD Software Solutions LLC) |
| .HCR | HydroCAD Stormwater Modeling System Rainfall Definition (HydroCAD Software Solutions LLC) |
| .HCR | Half-fold Card File |
| .HCR | IBM HCD/HCM Production Configuration |
| .HCSP | Content Server Web Page (Stellent, Inc.) |
| .HCSS | Hyper Color Swatch Set (SodaBush) |
| .HCT | Symantec Anti-Virus Live Update File (Symantec Corporation) |
| .HCU | HydroCAD Stormwater Modeling System Units Definition File (HydroCAD Software Solutions LLC) |
| .HCW | HTML Help Workshop Conversion Wizard Macro (Microsoft Corporation) |
| .HCX | Harvard Graphics Chart XL Chart (Harvard Graphics) |
| .HD | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HD2 | Curious Labs Poser Hand File |
| .HDA | HotDocs Auto-Assemble File (Matthew Bender & Company, a member of the LexisNexis Group) |
| .HDAT | vStaticIP Data File (Phil Doyle a.k.a. MrJolly) |
| .HDAT | Objective Analysis Package Data File |
| .HDB | ACT! History File (Best Software CRM Division) |
| .HDB | Nero HD-Backup (Nero AG) |
| .HDC | HD Tach Benchmark File (Simpli Software Inc.) |
| .HDC | HelloDOC Medical Software File (IMAGINE Éditions) |
| .HDD | HelloDOC Medical Software File (IMAGINE Éditions) |
| .HDD | Parallels Desktop for Mac Hard Disk Drive Image (Parallels, Inc.) |
| .HDF | Amiga Hardfile Image |
| .HDF | Hierarchical Data Format File |
| .HDF | Procomm Plus Alternate Download File Listing |
| .HDF | Help Development Kit Help File |
| .HDI | AutoCAD Heidi Device Interface (Autodesk, Inc.) |
| .HDI | HelloDOC Medical Software File (IMAGINE Éditions) |
| .HDI | HotDocs Auto-Install File (Matthew Bender & Company, a member of the LexisNexis Group) |
| .HDK | OS/2 Saved SKF Format File (IBM) |
| .HDK | MAXI Disk Disk Image (Herne Data Systems Ltd.) |
| .HDL | HotDocs Library File (Matthew Bender & Company, a member of the LexisNexis Group) |
| .HDL | Procomm Plus Alternate Download File Listing |
| .HDL | Giza Specifier Hidden Line Drawings (20-20 Technologies) |
| .HDM | Handheld Markup Language File |
| .HDML | Handheld Markup Language File |
| .HDMOV | QuickTime HD Movie (Apple Inc.) |
| .HDMP | WinXP Trouble Report |
| .HDO | Helpdesk-One File |
| .HDP | Magix Music/Video |
| .HDP | HDL Designer Project File (Mentor Graphics Corp.) |
| .HDR | Apollo HDRU |
| .HDR | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HDR | ArcInfo Binary (Environmental Systems Research Institute, Inc. (ESRI)) |
| .HDR | ArcView Header File (ESRI) |
| .HDR | Egret Data File |
| .HDR | MicroSim PCBoard Hole-Drill Schedule Report |
| .HDR | PC-File+ Database Header |
| .HDR | Photoshop (Adobe Systems Incorporated) |
| .HDR | Procomm Plus Message Header |
| .HDR | InstallShield Setup Header (Acresso Software Inc.) |
| .HDR | Photomatix HDR Image (HDRsoft) |
| .HDR | Radiance HDR Graphics Data |
| .HDRU | Apollo HDRU |
| .HDS | Hierarchical Data System |
| .HDS | XMap Hierarchical Dataset (Delorme) |
| .HDV | Formula 1 Car Race 2001 Season01 Vehicles Arrows File |
| .HDW | Harvard Graphics Draw Vector Graphics (Harvard Graphics) |
| .HDX | Help Index |
| .HE5 | Hierarchical Data Format Release 5 |
| .HEA | Fifa 2001 Data Feart Legal Screeen |
| .HEAD | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HEADER | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HEADERS | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HEARTS | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HEARTSSAVE-MS | Hearts Saved Game (Microsoft Corporation) |
| .HEAVYSIGH | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HEB | DEcomp 3D Scene Data (H|H/G Family of Corporations) |
| .HEC | Grafic Pvquan Quant File |
| .HED | ReliaSoft RG |
| .HED | Hi-Eddi |
| .HED | HighEdit Document |
| .HEH | Scarlett Expert System Compiler Facts File |
| .HEIDELB | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HEL | Hellbender Saved Game (Microsoft Corporation) |
| .HELI | RealFlight Radio Control Airplane Description (Knife Edge Software) |
| .HELLFONT | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HELLO | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .help | UNIX Help File |
| .HELP | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HELPER | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HELPSCREEN | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HEP | Novell NetWare Help Librarian Data File |
| .HEP | HostExplorer Telnet Session Profile (Hummingbird Ltd.) |
| .HER | Grafic GIF File |
| .HERALD | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HERBS1 | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HERBS2 | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HERBS3 | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HERBS4 | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HERBS5 | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HERE | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HERMETICA | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HES | Hudson Entertainment Sound |
| .HESSIAN | Insight II Hessian File (Accelrys Software Inc.) |
| .HESSIANX | Insight II Hessian File (Accelrys Software Inc.) |
| .HEX | HUGO Game File |
| .HEX | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HEX | SPLITGRADE Upgrade File (Heiland electronic GmbH) |
| .HEX | Hex Dump |
| .HEX | Magellan GPS Receiver Flash Upgrade File (Thales Navigation, Inc.) |
| .HEX | Macintosh BinHex 2.0 File |
| .HEX | Smart Touch Analyze and Retrieve Tool (START) Classic Operator Software Update (HySecurity) |
| .HEY | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HEY2 | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HEYCOOLMAN | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .hf | UNIX Help File |
| .HFA | ERDAS IMAGINE Hierarchical File Architecture (Leica Geosystems , LLC) |
| .HFB | Hell Fighter Battle File (David Peterson) |
| .HFB | Ralcgm File |
| .HFD | HotDocs Form Document (Matthew Bender & Company, a member of the LexisNexis Group) |
| .HFI | HP Font Info |
| .HFO | Hollywood FX Object File (Pinnacle Systems, Inc.) |
| .HFP | Harry's Filters Filter Preset (Harald Heim (The Plugin Site)) |
| .HFS | Macintosh Disk Image on CD |
| .HFT | HotDocs Form Template (Matthew Bender & Company, a member of the LexisNexis Group) |
| .HFT | HaftiX Cross-Stitch Pattern (GRZELA Grzegorz Zochowski) |
| .HFV | Simulated Macintosh Volumes on PC Hard Drive |
| .HFX | HotFax Fax (Smith Micro Software) |
| .HFX | Hollywood FX Special Effects File (Pinnacle Systems, Inc.) |
| .HFX | US Robotics Rapid Comm Voice Data File |
| .HFX | Harvard Graphics F/X File (Harvard Graphics) |
| .HFZ | Pinnacle Studio HollywoodFX Plug-In Video Editing File (Pinnacle Systems, Inc.) |
| .HG1 | Hellgate: London Saved Game (Flagship Studios, Inc.) |
| .HGC | PC Fold Molecule Secondary Structure |
| .HGH | Star Wars - Tie Fighter High Score |
| .HGH | PDP-10 High Segment of a Two-Segment Program |
| .HGL | DN Highlight Groups Definition |
| .HGL | HP Graphics Language (Plotter File) |
| .HGP | HighGrow (Legal Marijuana Growing Game) Plant File (Slick Software) |
| .HGS | HighGrow Virtual Seed File |
| .HGT | Shuttle Radar Topography Mission Data (SRTM) |
| .HH | C++ Header |
| .HH | HammerHead Drumloop File |
| .HH | Help Topic Map File |
| .HHA | HyperHub Archive (Oracle) |
| .HHC | HTML Help Table of Contents (Microsoft Corporation) |
| .HHC | TurboTax Contents File (Intuit) |
| .HHH | Power C Precompiled Header |
| .HHK | HTML Help Index (Microsoft Corporation) |
| .HHL | Visual Basic File |
| .HHP | HTML Help Workshop Project (Microsoft Corporation) |
| .HHS | HTML Help Samples (Microsoft Corporation) |
| .HHS | HyperHub Subkit (Oracle) |
| .HHTML | Realmedia Adstream HTML File |
| .HI | High Scores |
| .HI | Spy-CD CD Search Index File |
| .HI1 | Spy-CD CD Search Database File |
| .HI2 | Spy-CD CD Search Database File |
| .HI4 | Spy-CD CD Search Database File |
| .HIA | Spy-CD CD Search Database File |
| .HIB | Spy-CD CD Search Database File |
| .HIC | HicEst Script (Georg Petrich, HicEst Instant Prototype Computing) |
| .HIC | Spy-CD CD Search Database File |
| .HID | Sony Ericsson Configuration Archive |
| .HIF | Quicken On-line File (Intuit Inc.) |
| .HIG | High Scores |
| .HIGH | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HIH | Spy-CD CD Search Database File |
| .HIHAT | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HIL | Hi HelpIndex Language File |
| .HIM | Spy-CD CD Search Database File |
| .HIN | Spy-CD CD Search Database File |
| .HIN | HyperChem Molecule File (Hypercube, Inc.) |
| .HINT | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HINTS | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HINTS2 | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HIP | HiP Compressed File |
| .HIP | Spy-CD CD Search Database File |
| .HIPS | Bitmap Graphic |
| .HIQ | Spy-CD CD Search Database File |
| .HIR | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HIR | Hidden Icon Resource |
| .HIR | C64 Hires Bitmap Graphic |
| .HIR2 | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HIS | DN History of Executing/Viewing/Editing |
| .HIS | SOBEK Simulation History (WL | Delft Hydraulics) |
| .HIS | Spy-CD CD Search Database File |
| .HIS | Insight II Dynamics Trajectory History File (Accelrys Software Inc.) |
| .HIST | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HISTORY | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HIT | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HIT | The Sims Sound File (Electronic Arts (Maxis)) |
| .HIT | Nonags Dialog Killer Data File |
| .HIT | HitPlayer Audio File |
| .HIV | W32/SillyFDC-AS |
| .HIV | Windows NT Registry Hive (Microsoft Corporation) |
| .HIV | RegShot Registry Hive File (TiANWEi) |
| .HIW | Spy-CD CD Search Database File |
| .HIX | System SYSUTIL File |
| .HIZ | Spy-CD CD Search Database File |
| .HJT | TreePad Hypertext Database File (Freebyte) |
| .HK5 | ACT! Database File (Best Software CRM Division) |
| .HKC | HTML-KIT Auto Complete Short-cuts |
| .HKI | WinHki Compressed Archive (Hanspeter Imp) |
| .HKI1 | WinHki Compressed File |
| .HKI2 | WinHki Compressed File |
| .HKI3 | WinHki Compressed File |
| .HKS | HTML-Kit Plug-in (HTML-Kit.com) |
| .HKT | egseing RB HK Data |
| .HL$ | Compressed DOS Help File (Microsoft Corporation) |
| .HLB | VAX Help Library |
| .HLD | Structural Desktop Saved Data (Hold File) (Structural Desktop, Inc.) |
| .HLF | FAR Manager Help File (FAR Group) |
| .HLF | BASIC QuickBAS QuickB01 File |
| .HLI | MOJO 620 Logo (TDK) |
| .HLL | Boulderdash Game File |
| .HLM | Winhelp Vbhilfe File |
| .HLN | MicroStation Hidden Line File (Bentley Systems, Incorporated) |
| .HLP | Windows Help File (Microsoft Corporation) |
| .HLP | Stata Statistical Software Help File (Stata Corporation) |
| .HLP | HP-95LX Help File |
| .hlp | UNIX Help File |
| .HLP | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HLP | Advisor Help File (Microsoft Corporation) |
| .HLX | ATI Radeon Video Driver Support File |
| .HLX | Multi-Edit Help File |
| .HLX | Visual C++ Syntax Coloring Instructions (Microsoft Corporation) |
| .HLX | Hollex Cartridge Atari Cartridge Image File |
| .HLX | Hyperlatex File |
| .HLX | Help Magician Help Text File (Software Interphase, Inc.) |
| .HLZ | Multi-Edit Packed Help File |
| .HM | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HM | Windows Help Context IDs used by MAKEHM.EXE. |
| .HM2 | Help & Manual Ver 2 Help File Project (EC Software GmbH) |
| .HM3 | Help & Manual Ver 3 Help File Project (EC Software GmbH) |
| .HMA | ATRAC3plus Encoded Audio File (Sony) |
| .HME | Smartphone Theme File |
| .HMF | HOOPS Metafile (Tech Soft America) |
| .HMI | Descent Human Machine Interfaces MIDI File |
| .HMK | Hallmark Card Studio File (Creative Home) |
| .HMM | Procomm Plus Alternate Mail Read Option Menu |
| .HMP | 3D GameStudio Terrain Entity (Conitec Datasystems, Inc) |
| .HMP | Descent Human Machine Interfaces MIDI File |
| .HMP | Frontier: First Encounters Music File |
| .HMP | Technics Sx KN 6000 Keyboard Home Page File |
| .HMP | Help Magician Help Project File (Software Interphase, Inc.) |
| .HMR | GeoTIFF Bitmap File (Bentley Systems, Incorporated) |
| .HMS | Stentura 8000 or Stentura 8000LX Deposition File |
| .HMS | HMS Archiware File |
| .HMS | MS SMS Inventory File |
| .HMSKIN | Help & Manual Ver 5 Help File Skin (EC Software GmbH) |
| .HMT | HighMAT (Microsoft Corporation) |
| .HMW | Homeword for DeskMate |
| .HMX | MixlleniumEngine (Haydee) Web Server Module Template File |
| .HMX | Help & Manual Ver 4 Help File Project (EC Software GmbH) |
| .HMXP | Help & Manual Ver 5 Help File Uncompressed XML Project (EC Software GmbH) |
| .HMXZ | Help & Manual Ver 5 Help File Compressed XML Project (EC Software GmbH) |
| .HM~ | Help&Manual Backup Help File Project |
| .HNC | CNC Program File Heidenhain Dialog |
| .HNC | NoteCenter Note File (Domas Savickas) |
| .HND | HelpNDoc Project File (IBE Software) |
| .HND | Hallo Northern Sky (HNSKY) Deep Sky Database File (Han Kleijn) |
| .HNE | NoteCenter Encrypted Note File (Domas Savickas) |
| .HNF | Humax Receiver Settings |
| .HNS | Hallo Northern Sky (HNSKY) Settings (Han Kleijn) |
| .HNV | TheWord & Bible Companion Hebrew Names Version Bible |
| .HO | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HO | Knowledge Explorer Knowledge Representation Hierarchy Outline |
| .HO | Magix Music/Video |
| .HOB | Star Trek: Birth of the Federation Ship Graphic (Atari) |
| .HOC | High Octane Race Course (Fishstick Games) |
| .HOCKEY | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HOD | Homeworld Hardpoint/Object Data (Sierra Entertainment, Inc.) |
| .HOF | Hall Of Fame |
| .HOG | Descent Mission File |
| .HOG | Lucas Arts Dark Forces WAD File |
| .HOL | Personal Paint Dutch Language User Interface File (Amiga) |
| .HOLES | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HOLLY | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HOME | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HOME1 | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HOME2 | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HOOD | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HOP | Hippon Protected File (Hippon SAS) |
| .HOR | Horoscope |
| .HORIZON1 | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HORIZON2 | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HORN | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HORNPIPE | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HOT | Mosaic Internet Address |
| .HOT | eFax Messenger Fax (j2 Global Communications, Inc.) |
| .HOT | The Sims Sound File (Electronic Arts (Maxis)) |
| .HOTFONT | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HOTSPOT | Homeworld Cursor Informaiton (Sierra Entertainment, Inc.) |
| .HOW | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HP | Thor Database Primary Hash File |
| .HP | HP Graphics Language (Plotter) |
| .HP$ | NTgraph Visual C Wizzard File |
| .HP- | HP Distribution Binary File |
| .HP-UX | HP-UNIX File |
| .HP8 | HP NewWave Write ASCII Roman8 Character Set |
| .HP? | LoseThos C+ Header File (Terry A. Davis) |
| .HPD | Harry Potter Related |
| .HPD | HotDocs PDF Document (Matthew Bender & Company, a member of the LexisNexis Group) |
| .HPD | HP Document (Hewlett-Packard Development Company, L.P.) |
| .HPF | PageMaker HP LaserJet Font (Adobe Systems Incorporated) |
| .HPF | NetHelp2 Project File (Netscape) |
| .HPF | HotLine Partial Download File |
| .HPG | Hide Photos Encrypted Photo Container (Bolide Software) |
| .HPG | HP Graphics Language (Plotter) |
| .HPGL | HP Graphics Language (Plotter) |
| .HPH | Designer Graphics System2 File |
| .HPI | GEM Font Information |
| .HPI | Hemera Photo-Object Image (Hemera Technologies Inc.) |
| .HPI | Total Annihilation Saved Game |
| .HPIC | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HPJ | HP LaserJet Print-to-File |
| .HPJ | Help Project File |
| .HPJ | Visual Basic Help Project |
| .HPK | HPXUpgrade Service Pack Fileset (Haliplex Communication Systems) |
| .HPK | Compressed Archive |
| .HPL | HP Graphics File |
| .HPLJ | Hewlett-Packerd LaserJet Vector Image |
| .HPM | Procomm Plus Alternate Main Menu for Privileged Users |
| .HPM | HP NewWave Emm Text |
| .HPM | Quaestor 1.x High Performance Map |
| .HPM | Procomm Plus Alternative Menu |
| .HPP | Zortech C++ Header |
| .HPP | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HPP | C++ Builder 6 Program Header (Borland Software Corporation) |
| .HPP | C++ Program Header |
| .HPP | Printer Control Language Vector Image (Hewlett-Packard) |
| .HPP | InfoMgr Database File (RESystems, Inc.) |
| .HPPCL | Hewlett-Packard Printer Control Language Vector Image |
| .HPR | RoboHELP Configuration File |
| .HPR | ATLAS.ti 4.x Project File (Scientific Software Development) |
| .HPR5 | ATLAS.ti 5.0 Project File (Scientific Software Development) |
| .HPRJ | Heroglyph Project File (proDAD GmbH) |
| .HPRT | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HPS | HP HPS Digital Sender Information (Hewlett-Packard Development Company, L.P.) |
| .HPT | HotDocs PDF Template (Matthew Bender & Company, a member of the LexisNexis Group) |
| .HPUX | HP-UNIX File |
| .HPW | CompuServe Home Page Wizard |
| .HPW | HP Word Document (Hewlett-Packard Development Company, L.P.) |
| .HP_ | Winhelp Compressed File |
| .HP~ | V-help File |
| .HQP | CP/M Disc Utility Information |
| .hqx | Macintosh BinHex 4 Compressed Archive |
| .HR | TRS 80 Graphic |
| .HR2 | Curious Labs Poser Hair File |
| .HR5 | Heredis 2000 Family History File (BSD CONCEPT) |
| .HRC | SoftImage Model Geometry File |
| .HRF | Hitachi Raster Format Graphic |
| .HRH | C++ and Resources Common Header |
| .HRL | Herolab EasyWin32 |
| .HRM | Procomm Plus Alternate Main Menu |
| .HRM | Netmino File |
| .HRP | AviSys Bird Watcher Database (Jerry Blinn) |
| .HRP | Handy Recovery Recovered Partion Information (SoftLogica LLC.) |
| .HRT | Hornet Packer Module/Song |
| .HRU | HRU Bitmap |
| .HRV | Personal Paint Croatian Language User Interface File (Amiga) |
| .HRX | Herolab EasyWin32 |
| .HRZ | Slow Scan Television (SSTV) |
| .HS | RAZR Flex File (Motorola, Inc.) |
| .HS | Literate Haskell Source Code File |
| .HS | HSnapshot Screen Snapshot (PCNetWork) |
| .HS | Hugs Source Code |
| .HS2 | Postering Monochrome Image |
| .HS2 | HyperRESEARCH (ResearchWare, Inc.) |
| .HS3 | HyperRESEARCH (ResearchWare, Inc.) |
| .HSA | Hagaki Studio Address Book (Microsoft Corporation) |
| .HSB | HandStory Suite eBook File (SJ NAMO, Inc.) |
| .HSB | HALion Sampler File (Steinberg Media Technologies GmbH.) |
| .HSBOY | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HSC | HSC Tracker 2-op FM Music File |
| .HSC | HYSYS Simulation (Aspen Technology, Inc.) |
| .HSC | HelpScribble Project Source (JGsoft - Just Great Software) |
| .HSD | Hagaki Studio Document (Microsoft Corporation) |
| .HSD | HSD+CP Aero-HSD Configuration File (Thrane & Thrane) |
| .HSE | Dreamweaver Snippet |
| .HSF | Lizard Protector Web Content Security Protected Web Content (LockLizard Limited) |
| .HSF | HOOPS Stream File (Tech Soft America) |
| .HSH | IIS NNTP Hash File (Microsoft Corporation) |
| .HSI | HSI JPEG Bitmap |
| .HSI | Handmade Software Graphic File |
| .HSK | Nimbus 7 SAMS Data File |
| .HSM | Assembly Language Header - University of Waterloo Engineering Convention |
| .HSM | The Sims Sound File (Electronic Arts (Maxis)) |
| .HSP | HomeSite WWW Page Project |
| .HSP | HSC Packed |
| .HSQ | Data File Associated with Qaz Trojan |
| .HSQ | CAST Application Mining Suite |
| .HSR | RezeptAssist Import and Export File |
| .HSR | Hero Screen Recorder Screen Capture File (Beijing Herosoft Zongheng Network Technology Co., Ltd) |
| .HSS | Dreamweaver Snippet |
| .HSS | Photoshop Hue/Saturation Information (Adobe Systems Incorporated) |
| .HST | Yahoo! Instant Messenger History |
| .HST | Symantec Anti-Virus Live Update File (Symantec Corporation) |
| .HST | Procomm Plus History File |
| .HST | Netscape History File |
| .HST | Image Alchemy Handmade Software Graphics Histogram |
| .HST | Host File |
| .HST | VGA Planets Game File (Tim Wisseman) |
| .HST | WordPerfect (Corel Corporation) |
| .HST | Corel QuickCorrect and Speller History File |
| .HST | History File |
| .HSX | Health and Safety Xpert Project (HBXL Construction Software) |
| .HSZ | Handyscript Skin (Ventris, Inc.) |
| .HT | BrailleNote Visual Display File (Pulse Data International Ltd.) |
| .HT | HyperTerminal Data File (Hilgraeve Inc.) |
| .HT3 | HTML File |
| .HTA | Hypertext Application |
| .HTA | Hemera Thumbnail Archive (Hemera Technologies Inc.) |
| .HTA | Tonline BSW4 File |
| .HTACCESS | Apache Access Configuration |
| .HTB | HttpBrowser Database File |
| .HTC | HTML Component |
| .HTD | HyperTRANSCRIBE Project File (ResearchWare, Inc.) |
| .HTF | HTF Sounding File |
| .HTF | Virtual Hypertext Font |
| .HTF | WebBase File |
| .HTI | Win Help Related File |
| .HTI | WebBase File |
| .HTM | Hypertext Markup Language |
| .HTMENX | egis Encrypted HTM File (HiTRUST Inc.) |
| .HTML | Mozilla (Netscape) Bookmark File (Mozilla.org) |
| .HTML | Hypertext Markup Language |
| .HTMLENX | egis Encrypted HTML File (HiTRUST Inc.) |
| .HTMLS | Server-side HTML File |
| .HTN | Micrografx Picture Publisher 8 printstyles file |
| .HTP | honestech Video Editor Project File (Honest Technology,) |
| .HTR | People Putty Haptek Character (Haptek, Inc.) |
| .HTR | Motion Analysis Software Skeletal File |
| .HTRI | HTRI Xchanger Suite Data Input File (Heat Transfer Research, Inc.) |
| .HTS | Troj/DelSpy-E |
| .HTT | Hypertext Template File (Microsoft Corporation) |
| .HTX | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HTX | Extended Hypertext Template |
| .HTX | MS FrontPage Database Results HTML-like query script. |
| .HTZ | HTML Editor Archive |
| .HU | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HUD | HUD Maker File (Radio Tree Productions, Inc.) |
| .HUF | Huffman Encoded/Compressed File |
| .HUH | HydroCAD Stormwater Modeling System Unit Hydrograph (HydroCAD Software Solutions LLC) |
| .HULL | Halflife Map Collision Hull File |
| .HUN | Dataview File |
| .HUN | Personal Paint Hungarian Language User Interface File (Amiga) |
| .HUS | Husqvarna Designer Embroidery Machine Format (Husqvarna Viking) |
| .HUY | Eto Dlia Vas |
| .HVA | Tiberian Sun Voxel Animation Control File (TiberiumSun.com) |
| .HVD | chosenOS HoverNews Skin File |
| .HVD | CMT Surveyor's Assistant 1.x/2.0x Job |
| .HVD | ISIS Hviews File |
| .HVD | HoverDesk Theme File (Hover Inc.) |
| .HVD | HerdView Event Data File |
| .HVX | LightWave 3D Hypervoxel (NewTek) |
| .HW | Stanford University EPGY Homework |
| .HWCFG | VersaPro Hardware Configuration File |
| .HWD | Hollywood Presentation File |
| .HWL | Corel Shared Writing Tools 9.0 File |
| .HWL | HttpWatch HTTP Watch Log (Simtec Limited) |
| .HWL | Hangman Deluxe Word List |
| .HWM | Hillwalker/MapWise/Alpiniste/PhotoMaps Own Raster Map Parameters (ISYS Computers) |
| .HWP | Hangul Word Processor File (Haansoft) |
| .HWPROJ | Visual Studio .NET Help Project (Microsoft Corporation) |
| .HWR | Hillwalker/MapWise/Alpiniste/PhotoMaps ISYS Route Card (ISYS Computers) |
| .HX | THOR Database Cross-reference Hash File |
| .HX | EARS Component File |
| .HX | haXe Source Code (Motion-Twin) |
| .HX | SurRender3D Database File |
| .HXC | Help 2 Project/Collection File (Microsoft Corporation) |
| .HXCONV | Huelix Audio Converter Session Information (Huelix Solutions Private Ltd) |
| .HXD | Help 2 Validator File (Microsoft Corporation) |
| .HXF | Help 2 Include File (Microsoft Corporation) |
| .HXG | Help 2 Filter Cache (Microsoft Corporation) |
| .HXH | Help 2 Merged Hierarchy (Microsoft Corporation) |
| .HXI | Help 2 Compiled Help File (Microsoft Corporation) |
| .HXK | Help TOC/Index File |
| .HXK | Help 2 Keyword Index (Microsoft Corporation) |
| .HXL | Help 2 Registered Namespaces List (Microsoft Corporation) |
| .HXM | Procomm Plus Alternate Protocol Selection Menu for All Users |
| .HXM | Descent2 HAM File |
| .HXML | haXe Make File (Motion-Twin) |
| .HXS | Help 2 Compiled Help File (Microsoft Corporation) |
| .HXT | Help TOC/Index File |
| .HXT | Help 2 Table of Contents (Microsoft Corporation) |
| .HXV | Help 2 Virtual Topic Definition (Microsoft Corporation) |
| .HXW | Help 2 Merged Keyword Index (Microsoft Corporation) |
| .HXX | C++ Header |
| .HX_ | C Poet Compressed Disk1 File |
| .HY1 | Ventura Publisher Hyphenation Algorithm |
| .HY2 | Ventura Publisher Hyphenation Algorithm |
| .HYC | WordPerfect Hyphenation File (Corel Corporation) |
| .HYD | WordPerfect for Windows Hyphenation Dictionary (Corel Corporation) |
| .HYM | Scandata 3D Scanner File (Hymarc, Inc.) |
| .HYP | Atari ST Guide Hypertext Document |
| .HYP | Hyper Compressed Archive |
| .HYP | Acrobat Spelling File (Adobe Systems Incorporated) |
| .HYP | Hyphenation File |
| .HYPERCARD | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HYPERXCMD | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HYPHENATOR | Unknown Apple II File (found on Golden Orchard Apple II CD Rom) |
| .HYS | Globe HySales Client File (Globe Interactive) |
| .HYS | TriboIndenter Air Indent Electrostatic Force Constant Setting (Hysitron Incorporated) |
| .HYS | Smart Touch Analyze and Retrieve Tool (START) New Generation Operator Software Update (HySecurity) |
| .HZ | Chinese Text |
| .HZF | Neosat Fixes (Neosat USA) |
| .HZF | Home Inspector Pro Client Inspection (Home Inspection Software) |
| .HZO | CrossWorks Object File (Rowley Associates Limited) |
| .HZX | CrossWorks Executable File (Rowley Associates Limited) |
| .H_ | Winhelp Compressed File |
| .H__ | C++ Header Seldom used C++ Header (same as H++ and H) |