A USB device being inserted into a USB port.
An example of a USB is the interface used to upload pictures from a digital camera to a computer.
Origin of USBU(niversal) S(erial) B(us)
usb - Computer Definition
A serial bus with a data transfer rate of 12 Mbps for connecting a microcomputer to peripherals such as keyboards, mice, printers, and digital cameras through a single, general purpose port. USB is a considerable improvement over the RS-232 interface, but does not compare favorably with IEEE 1394, also known as FireWire in the Apple computer domain. See also 1394, bus, FireWire, IEEE, microcomputer, peripheral, port, RS-232, and serial.
(2) (Universal Serial Bus) The most widely used hardware interface for attaching peripherals to a computer. There are at least two USB ports on laptops and four on desktop computers, while USB "hubs" provide more connections (see below). After appearing in 1997, USB became the standard for connecting keyboards, mice, printers and hard drives, eventually replacing the PC's serial and parallel ports and the Apple Desktop Bus on Macs (see serial port, parallel port and ADB). Supporting 127 peripheral units on a single computer, devices can be plugged and unplugged while the computer is on, although a manual "eject" is required before removing. This "hot swappable" feature, combined with easy-to-reach ports on the front of the computer case, gave rise to the ubiquitous flash drive for transport (see USB drive). See PoweredUSB, USB device class, USB OTG, USB switch and USB toy.