| Extension | File Description |
| .HBU | Uncommon Files |
| .HBV | Uncommon Files |
| .HBW | Uncommon Files |
| .HBX | Encoded Files |
| .HBY | Uncommon Files |
| .HBZ | Uncommon Files |
| .HC | Uncommon Files |
| .HC0 | Uncommon Files |
| .HC1 | Uncommon Files |
| .HC2 | Uncommon Files |
| .HC3 | Uncommon Files |
| .HC4 | Uncommon Files |
| .HC5 | Uncommon Files |
| .HC6 | Uncommon Files |
| .HC7 | Uncommon Files |
| .HC8 | Uncommon Files |
| .HC9 | Uncommon Files |
| .HCA | Uncommon Files |
| .HCB | Uncommon Files |
| .HCC | Data Files |
| .HCD | Uncommon Files |
| .HCE | Data Files |
| .HCF | Developer Files |
| .HCG | Uncommon Files |
| .HCH | Uncommon Files |
| .HCI | Data Files |
| .HCJ | Uncommon Files |
| .HCK | Uncommon Files |
| .HCL | Data Files |
| .HCM | Uncommon Files |
| .HCN | Uncommon Files |
| .HCO | Uncommon Files |
| .HCOM | Uncommon Files |
| .HCP | CAD Files |
| .HCQ | Uncommon Files |
| .HCR | Page Layout Files |
| .HCS | Uncommon Files |
| .HCSP | Uncommon Files |
| .HCSS | Uncommon Files |
| .HCT | Uncommon Files |
| .HCU | Data Files |
| .HCV | Uncommon Files |
| .HCW | Uncommon Files |
| .HCX | Data Files |
| .HCY | Uncommon Files |
| .HCZ | Uncommon Files |
| .HD | Uncommon Files |
| .HD0 | Uncommon Files |
| .HD1 | Uncommon Files |
| .HD2 | 3D Image Files |
| .HD3 | Uncommon Files |
| .HD4 | Uncommon Files |
| .HD5 | Uncommon Files |
| .HD6 | Uncommon Files |
| .HD7 | Uncommon Files |
| .HD8 | Uncommon Files |
| .HD9 | Uncommon Files |
| .HDA | Data Files |
| .HDAT | Uncommon Files |
| .HDB | Database Files |
| .HDC | Uncommon Files |
| .HDD | Disk Image Files |
| .HDE | Uncommon Files |
| .HDF | Data Files |
| .HDG | Uncommon Files |
| .HDH | Uncommon Files |
| .HDI | Data Files |
| .HDJ | Uncommon Files |
| .HDK | Misc Files |
| .HDL | Data Files |
| .HDM | Web Files |
| .HDML | Web Files |
| .HDMOV | Video Files |
| .HDMP | System Files |
| .HDN | Uncommon Files |
| Extension | File Description |
| .HDO | Uncommon Files |
| .HDP | Audio Files |
| .HDQ | Uncommon Files |
| .HDR | Raster Image Files |
| .HDRU | Uncommon Files |
| .HDS | Data Files |
| .HDT | Uncommon Files |
| .HDU | Uncommon Files |
| .HDV | Uncommon Files |
| .HDW | Uncommon Files |
| .HDX | Uncommon Files |
| .HDY | Uncommon Files |
| .HDZ | Uncommon Files |
| .HE0 | Uncommon Files |
| .HE1 | Uncommon Files |
| .HE2 | Uncommon Files |
| .HE3 | Uncommon Files |
| .HE4 | Uncommon Files |
| .HE5 | Uncommon Files |
| .HE6 | Uncommon Files |
| .HE7 | Uncommon Files |
| .HE8 | Uncommon Files |
| .HE9 | Uncommon Files |
| .HEA | Uncommon Files |
| .HEAD | Uncommon Files |
| .HEADER | Uncommon Files |
| .HEADERS | Uncommon Files |
| .HEARTS | Uncommon Files |
| .HEARTSSAVE | Game Files |
| .HEAVYSIGH | Uncommon Files |
| .HEB | Uncommon Files |
| .HEC | Uncommon Files |
| .HED | Uncommon Files |
| .HEE | Uncommon Files |
| .HEF | Uncommon Files |
| .HEG | Uncommon Files |
| .HEH | Uncommon Files |
| .HEI | Uncommon Files |
| .HEIDELB | Uncommon Files |
| .HEJ | Uncommon Files |
| .HEK | Uncommon Files |
| .HEL | Uncommon Files |
| .HELI | Uncommon Files |
| .HELLFONT | Uncommon Files |
| .HELLO | Uncommon Files |
| .HELP | System Files |
| .HELPER | Uncommon Files |
| .HELPSCREEN | Uncommon Files |
| .HEM | Uncommon Files |
| .HEN | Uncommon Files |
| .HEO | Uncommon Files |
| .HEP | Uncommon Files |
| .HEQ | Uncommon Files |
| .HER | Uncommon Files |
| .HERALD | Uncommon Files |
| .HERBS1 | Uncommon Files |
| .HERBS2 | Uncommon Files |
| .HERBS3 | Uncommon Files |
| .HERBS4 | Uncommon Files |
| .HERBS5 | Uncommon Files |
| .HERE | Uncommon Files |
| .HERMETICA | Uncommon Files |
| .HES | Uncommon Files |
| .HESSIAN | Uncommon Files |
| .HESSIANX | Uncommon Files |
| .HET | Uncommon Files |
| .HEU | Uncommon Files |
| .HEV | Uncommon Files |
| .HEW | Uncommon Files |
| .HEX | Misc Files |
| .HEY | Uncommon Files |
| .HEY2 | Uncommon Files |
| .HEYCOOLMAN | Uncommon Files |
| .HEZ | Uncommon Files |
| .hf | Raster Image Files |
