What is Bitcoin?
Going right to the source, the following is a quote from Bitcoin’s main page:
“Bitcoin uses public-key cryptography, peer-to-peer networking,
and proof-of-work to process and verify payments. Bitcoins are sent (or
signed over) from one address to another with each user potentially
having many, many addresses. Each payment transaction is broadcast to
the network and included in the blockchain so that the included bitcoins
cannot be spent twice. (The blockchain is the distributed record of all
transactions involving bitcoins.) After an hour or two, each
transaction is locked in time by the massive amount of processing power
that continues to extend the blockchain. Using these techniques, Bitcoin
provides a fast and extremely reliable payment network that anyone can
use.”