USB-C, technically known as USB Type-C, is a 24-pin USB connector system, which is distinguished by its rotationally-symmetrical connector.
The USB Type-C Specification 1.0 was published by the USB Implementers Forum (USB-IF) and was finalized in August 2014. It was developed at roughly the same time as the USB 3.1 specification.
USB-C 3.1 cables are considered full-featured USB-C cables. They are electronically marked cables that contain a chip with an ID function based on the configuration channel and vendor-defined messages (VDM) from the USB Power Delivery 2.0 specification. Cable length should be ≤ 2 m for gen. 1 or ≤ 1 m for gen. 2. Electronic ID chip provides information about product/vendor, cable connectors, USB signalling protocol (2.0, gen. 1, gen. 2), passive/active construction, use of VCONN power, available VBUS current, latency, RX/TX directionality, SOP controller mode, and hardware/firmware version .
USB-C 2.0 cables do not have shielded SuperSpeed pairs, sideband use pins, or additional wires for power lines. Increased cable lengths up to 4 m are possible.
All USB-C cables must be able to carry a minimum of 3 A current (up to 60 W @20V) but can also carry high-power 5 A current (up to 100 W). All USB-C to USB-C cables must contain e-marker chips programmed to identify the cable and its current capabilities. USB Charging ports should also be clearly marked with capable power wattage.