USB-A: Most commonly used USB connector, typically found on one end of a USB cable. USB-B: A square-shaped connector, typically found on devices such as printers. USB-C: A newer, reversible connector that can handle higher power and data transfer rates. USB Micro-B: A smaller version of the USB-B connector, commonly found on older smartphones and other portable devices. USB Mini-B: Another smaller version of the USB-B connector, also commonly found on older portable devices.