USB, technology used to connect computers to peripheral devices, such as computer mouses and USB flash drives.
Introduced in 1996, the USB standard was developed by a number of American companies, including IBM, Intel Corporation, and Microsoft Corporation, as a simpler way of connecting hardware to personal computers (PCs). Before USB technology, a PC typically would have one or two serial ports, a parallel port, mouse and keyboard ports, and, in some cases, a joystick port. A USB port offered a standardized way to connect a wide range of devices while offering significant advantages in speed over other connection types.
Initially, adoption of USB technology was slow. Computer manufacturers hesitated to add the ports to their systems before USB-capable devices were widely available; at the same time, manufacturers of peripheral devices waited to market USB products before the ports became standard on new computers. In addition, operating systems had only minimal support when the technology was first introduced. The first generation of Apple Inc.’s iMac, introduced in 1998, changed this, however. By making a popular computer that used only USB ports, Apple essentially drove other manufacturers to adopt the standard. Since then most peripheral devices, such as printers, scanners, and keyboards, have used USB technology. The standard even led to development of new devices, such as portable USB flash drives, which replaced floppy disks.
USB technology has been steadily updated since it was introduced. Each revision has increased the speed of the connection while staying backward-compatible with older revisions. In addition, improved adapters have allowed users to connect older serial devices, such as network switches, to USB ports.