Definition: Encryption is a means of securing digital data using one or more mathematical techniques, along with a password or "key" used to decrypt the information.
Encryption is a method of scrambling data so that only authorized parties can decipher it. It is the process, or cryptographic transformation of data (including messages and code), of converting human-readable plaintext to incomprehensible text, known as ciphertext. Ciphertext conceals the data’s original meaning to prevent it from being known or used. The formulas used to encode and decode messages are called encryption algorithms, or ciphers.
In summary, encryption takes readable data and alters it so that it appears random. Encryption necessitates the use of a cryptographic key, which makes the cipher’s output unique.
When an unauthorized entity intercepts encrypted data, the imposter must guess which cipher the sender used to encrypt the message, as well as which keys were used as variables. Secure encryption will use keys that a third party will be extremely unlikely to decrypt or break the ciphertext using brute force - that is, guessing the key.
Data can be encrypted "at rest," when it is being stored, or "in transit," when it is being transmitted to another location.