None of the Apple iPad devices have a USB port. Apple has its own proprietary connecting ports on the iPads. Fourth-generation iPads and newer have lightning ports, whereas older iPads have an Apple 30-pin dock connector as their connecting ports.
Apple iPad now comes with a proprietary lightning connection to interface with the device. Although, there is no dedicated USB port, an individual can use a third-party lightning to USB adapter to connect USB devices to the iPad, but only a limited number of devices are supported. Using more devices requires the iPad to be jailbroke and use third-party applications.