©

The symbol for copyright, referring to the exclusive legal right of an author or publisher to publication, production, or sale of the rights to an original literary, dramatic, musical, or artistic work. I, Ray Horak, am the author of this original work, to which Wiley owns the copyright. Please don’t even think about violating their copyright.Thank you. Have a nice day.

The Greek letter delta, , is the symbol for change or difference, as in delta modulation.

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λ

• 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)
• University Corporation for Advanced Internet Development (UCAID)