Public Keys, Private Keys, and Addresses

Bitcoin uses a clever system from the field of cryptography to prove ownership without revealing secrets. It relies on a pair of mathematically linked keys: a private key and a public key. Think of it this way — your private key is like the key to a safe deposit box. Your public key (and the Bitcoin address derived from it) is like the box's mailing address: anyone can send something to it, but only the person with the key can open it and take things out.