Encryption is the process of converting information or data into a code, especially to prevent unauthorized access. It is the most effective way to achieve data security. To read an encrypted file, you must have access to a secret key or password that enables you to decrypt it.
Encryption has been used for centuries to protect sensitive information. One of the earliest known examples is the Caesar cipher, used by Julius Caesar to protect military communications.
Encryption is a fundamental technology in modern society, used to secure everything from online banking and e-commerce to government communications and personal data.