high definition

High definition or HD may refer to:

Visual technologies

Blu-ray Disc, the universal optical High Definition disc format
HD Photo, former name for the JPEG XR image file format
HDV, format for recording high-definition video onto magnetic tape
HiDef, 24 frames-per-second digital video format
High-Definition Multimedia Interface (HDMI), all-digital audio/video interface capable of transmitting uncompressed streams
High-definition television (HDTV), television signals and apparatus with higher resolution than their contemporary counterparts
Ultra-high-definition television, a further step in television resolution, but not a successor.
High-definition video, used in HD broadcasting, digital film, computer HD video file formats, and video games

Dolby TrueHD, lossless audio compression codec
DTS-HD Master Audio, lossless audio compression codec
High Definition Compatible Digital, discontinued digital audio optical disc format
High-definition audio, general marketing term for high fidelity audio products and services
Intel High Definition Audio, 2004 Intel specification for hardware and associated drivers for Personal computer audio
Wideband audio, also known as HD voice, is high definition voice quality for telephony audio