USB-C is the same as any other USB standard the only difference is the design. USB-C is the replacement of types A and B. Now you no longer have to do the USB flip because its universal. It supports up to 15 watts of power to external devices like thumb-drives and iOS devices (using lightning to USB-C cable available at Apple). They, like USBs A and B, are backward compatible with USB versions 2.0, 3.0, and 3.1. USB-C is nowhere as fast or powerful as Thunderbolt 3. Although some of the advantages include consuming less power which is helpful for portable devices like the MacBook.
How do they Work Together?
Since they use the same design the devices like the MacBook are able to implement them both into one port. For example on the 2016 MacBook Pro and up all of the ports are USB-C and Thunderbolt 3 compatible. So it doesn’t matter which port you plug in your external 4k display or your USB-C external drive. There is no more flipping and flopping because both are symmetrical so no matter which way you twist the port it will always go fit.