Computer file extensions - H

Updated: 07/13/2023 by Computer Hope

Below is a listing of each of the different file extensions that begin with the letter "H." If you are looking for a file extension that starts with a different letter, click the corresponding beginning letter below.

.HAR JSON (JavaScript Object Notation) formatted archive file, containing HTTP (hypertext transfer protocol) performance data.
.HBK Mathcad handbook file.
.HDL Procomm Plus alternate download file listing.
.HDR 1. Procomm Plus message header
2. High Dynamic Range file.
.HDX Help index.
.HEIC High Efficiency Image File format file.
.HEIF High Efficiency Image File format file.
.HEX Hex dump.
.HFI GEM HP font info.
.HGL HP graphics language graphic.
.HH C++ header.
.HHH Precompiled header for Power C.
.HHP Help data for Procomm Plus.
.HLP Files that contain the help feature used in Windows. Note: These files cannot be read from the MS-DOS command line.
.HPGL CAD (computer-aided design) file.
.HQX Apple Macintosh Binhex text conversion file. Compressed file extracted and used with various compression utilities.
.HSQ Data files associated with the Qaz trojan.
.HSS Photoshop hue and saturation information.
.HST 1. History file.
2. Procomm Plus history file.
3. Host file.
.HTA Hypertext application file that runs applications from HTML (hypertext markup language) document.
.HTM Web page files containing HTML.
.HTML Web page files containing HTML.
.HTT Microsoft Hypertext template file used with Microsoft Internet Explorer 4.0. The folder.htt is an example of this file type.