When Is USB C or the Successor To USB 3.1 Coming?

Does anybody know, this is something I wanted to discuss. How is it going to fit into old PC(s) will we all need adapters, will it be backward compatible such as USB 3.1 and 2.0? Because that really blows especially if you just built a new PC and now all your USB ports are outdated : / . So does anyone know when it's coming or how all this is going to work?

3.1 Type-C (the one that you can plug in both ways) is not backwards compatible
3.1 is backwards compatible
that is if i understand it correctly
and some motherboards already have it