If there is no one company behind bitcoin, who controls it? "If there is no one company behind bitcoin, who controls it?"  This is the question that many people new to bitcoin ask. What is the best way to convey to them how bitcoin works, and in a way that can be understood by non-techies.
Bitcoin operates based on a set of rules known as the Bitcoin protocol, which is defined by a consensus among its users.

The Bitcoin software is open source so anyone can contribute to its development, but in order for one to have any influence his modified software needs to be accepted by the users (so harmful code will be rejected).

The Bitcoin currency day-to-day bookkeeping is operated by a peer-to-peer network of computers running a Bitcoin software which follows the Bitcoin protocol. Virtually anyone can make his own computer part of this network.