End user convenience is the keynote of the universal serial bus (USB). The Plug...

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End user convenience is the keynote of the universal serial bus (USB). The Plug and Play (PnP) concept has simplified the process of installing certain types of hardware on existing PCs. However, configuration issues continue to plague end users with respect to legacy devices such as serial and parallel ports, keyboards, and mice. Port availability is one of the factors that have historically limited proliferation of peripherals, including modems, answering machines, scanners, and personal digital assistants. USB helps solve these problems by providing a uniform method of connecting a potentially large number of self-identifying devices through a single PC port.