PGP utilises cryptography, data reduction, and hashing methods in conjunction. It is comparable to other widely used encryption techniques as the Secure File Transfer Protocol (SFTP), that safeguards data in motion, Secure Sockets Layer (SSL), which authenticates network users, and Kerberos, which secures websites.

PGP makes use of the public key system, where each user has a private key that is known only to them and an individual encryption key that is known only to them. When a user sends a message to someone is using their key pair, it is encrypted, and when the recipient accesses it using their private key, it is decrypted. It uses a combination of asymmetric and symmetric key technology, private-key and public-key cryptography, and these techniques to encrypt data as it moves across networks.

PGP employs the following three steps:

First, PGP creates a massive, unguessable public encryption method that serves as the random session key. Second, The message is then secured during transmission by encrypting the session key using the recipient's public key. Anybody they want to send messages to has access to that key, which the recipient shares. Third, The message sender provides their session key, and the recipient uses their private key to decrypt the message.

Encrypting whole communications can take a while, but PGP uses a quicker technique to do it. PGP reduces the amount of plaintext data that needs to be stored and transmitted while also enhancing the security of the cryptographic system. The shortened version of the complete message is encrypted using the public key. Both are delivered to the receiver, who then decrypts the entire message using the private key to reveal the shorter key.

To convey digital signatures, PGP makes use of effective algorithms that result in a hash, or mathematical summary. The private key of the message sender encrypts the hash code, that can comprise usernames as well as other digital data. The recipient decrypts the hash using the message sender's public key, and if the result matches what the sender sent, it verifies that message was safely received.