JPEG (Joint Photographic Experts Group)

A graphics file format for editing still images, as well as

color facsimile, desktop publishing, graphic arts, and medical imaging. A symmetrical compression technique, JPEG is equally expensive, processor-intensive, and time consuming in terms of both compression and decompression. JPEG is a joint standard of the International Telecommunications Union (ITU-T T.81) and the International Organization for Standardization (ISO 10918-1). JPEG involves a lossy compression mechanism using discrete cosine transform (DCT). Compression rates of 100:1 can be achieved, although the loss is noticeable at that level. Compression rates of 10:1 or 20:1 yield little degradation in image quality. See also compression, DCT, GIF, ISO, ITU-T, lossy compression, PNG, and symmetric.

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• uniform dialing plan (UDP)
• Uniform Resource Identifier (URI)
• Uniform Resource Locator (URL)
• U-NII (Unlicensed National Information Infrastructure)
• uninterruptible power supply (UPS)
• unipolar
• United Nations/Electronic Data Interchange For Administration, Commerce, and Transport
• United Nations (UN)
• United States Computer Emergency Readiness Team (US-CERT)
• United States Digital Cellular (USDC)
• United States Independent Telephone Association (USITA)
• United States Telecom Association (USTA)
• United States Time Division Multiple Access (US TDMA)
• UNI (User Network Interface)
• universal ADSL (universal Asymmetric Digital Subscriber Line Lite)
• Universal Character Set (UCS)
• Universal Code (Unicode)
• Universal Coordinated Time (UTC)
• Universal International Freephone Number (UIFN)
• Universal Mobile Telecommunications System (UMTS)
• Universal Plug and Play (UPnP)
• universal serial bus (USB)
• universal service
• Universal Service Administrative Company (USAC)
• Universal Service Fund (USF)