Own protocol in browser

Question

I try to implement WebClientPrinter by Neodynamic. This library makes request by this format:

webclientprint:http://localhost:1294/wcp.axd?sid=cm50pdi0tyfsm0feejnzjtsk&wcppping

it is similar to this notation.

javascript: method()

My question is why browser know what to do with this protocol?

Answer 1

I find information about it, I hope it could be interesting to someone.

http://www.codeproject.com/Articles/332206/Custom-URL-Protocol-for-Invoking-Application