A private key is one of a pair of codes used to access files encrypted using a process known as public-key cryptography. This type of encryption system uses two keys — a public key that is available to the general public, and a private key which only the recipient of an encrypted file has. You need both keys to be able to access the encrypted file.
To access a bank safety deposit box, some banks require two keys — one held by the bank manager and the other carried by the customer. This is somewhat how private keys work in the digital world.
Other interesting terms…
