Universal Serial Bus (USB) is an industry standard that establishes specifications for cables and connectors and protocols for connection, communication and power supply (interfacing) between computers, peripherals, phones and other computers. A broad variety of USB hardware exists, including several different connectors such as miniUSB, microUSB, of which USB-C is the most recent.
Released in 1996, the USB standard is currently maintained by the USB Implementers Forum (USB-IF). There have been four generations of USB specifications: USB 1.x, USB 2.0, USB 3.x and USB4.
USB version 1.1 provides maximum speeds of up to 1.5 MB/s while the version 2.0 is about 40 times faster. The versions are backwards compatible and the speed is limited by the slower device. Transferring data may require drivers to be installed on the desktop computer but some phones offer "mass storage" mode which means they appear as thumb drives to the computer and no special drivers are needed.
In addition to their data transferring application, USB cables also carry an electric charge that can be used to power peripherals (such as USB mice or keyboards), and many mobile phones can be charged through their USB port.