HD
HD may refer to any of the following:
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1. HD is an initialism for hard drive, although you may also see it written as "HDD" for hard disk drive.
2. Short for high definition, HD describes a standard of digital video or audio. For video, it means 1280 x 720 pixels, or 720p on televisions. See the HDTV (High-Definition TeleVision) definition for further information and related links.
For audio, HD means sound with 16-bit depth and at least a 44.1 kHz sampling rate.
3. Short for high density, HD is a type of floppy diskette. See our high-density disk definition for further information. When describing a disc, "high density" describes HD DVDs (High Density Digital Versatile Discs).
4K resolution, 8K resolution, Computer acronyms, FHD, HDTV, HQ, QHD, SD, UHD