A standard type of USB connector, often found on phones, for connecting phones to computers and other devices.
The most common use is connecting a phone to a computer, although some phones support charging via USB and/or connecting the phone directly to a printer.
Some phones also have a proprietary way to support audio (for headsets) via this connector as well.
Mini-USB is a larger type of connector. The smaller Micro-USB connector had become more popular on newer phones.