Universal Serial Bus (USB)

USB was developed in 1995 by a consortium that included NEC, IBM, Intel and Microsoft, and was designed to allow simple connections between computers and other peripheral devices. With this in mind, the key features of the USB interface include the ability to connect devices without rebooting the PC (hot plugging), to deliver power to devices (bus-powering), and an upper limit of 127 devices using hubs.

All USB data transmission is controlled by the PC (host controlled) and no special interface controller is required. However, it is possible to expand a PCs USB capability with additional host controller boards.

The original standard, USB1.0 had a bandwidth of 12Mbit/s which also followed through into the USB 1.1 revision, giving a maximum throughput of 12MByte/s which was unsuitable for vision applications.

With the introduction of USB2.0 in 2001, the bus bandwidth increased to 480Mbit/s, making USB2.0 suitable for devices with high data rates like mass storage devices and CD writers.

USB 3.0 was first launched in November 2008. It is also called SuperSpeed USB for reaching speeds that are 10x that of USB 2.0. (June 2010).

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