This part will focus on the USB-C connector itself. Check out Part 1 for an overview of all the USB3.1 specs.

The USB Type-C connector is slightly larger than the micro-B connector. It has 24 pins in a radially symmetric pinout, making its orientation reversible. Unlike previous versions of the USB connectors, there is no physical distinction in the plug depending on the functionality supported by the port or plug. USB-C does it all.

The Type-C Spec is part of the USB3.1 Spec, as explained in Part 1. You can download the full USB3.1 specification from usb.org. Follow along with the USB Type-C Specification Release 1.2 in the USB Type-C folder.

Pinout

Taking a quick look at the pinout, the radial symmetry is obvious. The GND pins are always on the outside, and the VBUS pins are always four in from the outside. GND, VBUS, DP, DM, and SSTX/SSRX are all familiar from the USB3.0 spec. The new pins are CC, VCONN, and SBU.