| Abbreviation | Definition |
|---|---|
| HLP | Program online help information |
| HLX | Help file (MultiEdit) |
| HLZ | Packed help file (MultiEdit) |
| HMI | MIDI Music file |
| HMM | Alternate Mail Read option menu (Procomm Plus) |
| HMM | Procomm Plus Alternate Mail Read option menu |
| HMP | Music (MIDI) |
| HNC | CNC program files Heidenhain (?) dialog |
| HOF | Game data (best scores) |
| HP | Hewlett-Packard printers/plotters Printout file |
| HP | THOR database Primary Hash file |
| HP8 | Text in HP Roman8 character set |
| HPF | HP LaserJet fonts (PageMaker) |
| HPG | HPGL plotter file - Vector graphics |
| HPGL | Vector graphics (plotter file) (Hewlett-Packard Graphics Language) |
| HPI | Font information (GEM) |
| HPI | GEM Font information |
| HPI | High Pixel Image |
| HPJ | Help project (MS Help Compiler) |
| HPJ | Printed to file (HP LaserJet) |