| hfx | Hot Fax Data |
| hfx | Pinnacle Hollywood FX Effects Data |
| hfz | L3DT Compressed Heightfield Data |
| hgc | PC Fold Data |
| hgc | Zeus 5.0 Physical Data |
| hgc1 | eXtendable Wad Editor HGC1 Data |
| hgdata | Altair HyperGraph Data |
| hge | Hulixerian Game Engine Data |
| hgf | HomeGauge Form File |
| hgf | MOUSE Hydrological File |
| hgm | Sublime Text Data |
| hgt | SRTM Elevation Data |
| hgx | GenX Data |
| hgz | LOCUS Vertical Observation Data |
| hh | PLINK Heterozygous Haploid Data |
| hh7 | PCAnywhere Log Data |
| hha | Oracle HyperHub Archive |
| hhb | LIGPLOT Hydrogen-bonds Data |
| hhd | STSDAS GEIS Data |
| hhh | STSDAS GEIS Header |
| hhm | HHsearch Database |
| hhr | HHsearch Results |
| hhs | Oracle HyperHub Subkit |
| hi | MAME Highscore Data |
| hi1 | FindinSite Database |
| hi2 | FindinSite Database |
| hi3 | FindinSite Database |
| hi4 | FindinSite Database |
| hi5 | FindinSite Database |
| hi6 | FindinSite Database |
| hi7 | FindinSite Database |
| hi8 | FindinSite Database |
| hi9 | FindinSite Database |
| hia | Spy-CD Database |
| hib | HIPI Image Bundle |
