Encryption is the process of transforming readable data into an unreadable format so only authorized parties can understand it. It protects sensitive information from eavesdropping or tampering during storage or transmission. Modern encryption relies on mathematical algorithms and cryptographic keys to secure data. When properly implemented, encryption prevents attackers from learning the contents of intercepted messages. Many web systems use encryption to protect network traffic, passwords, and stored files. Without encryption, any intermediary between a client and server could read or modify the data.
how it works
Encryption algorithms can be symmetric, where the same key encrypts and decrypts data, or asymmetric, where different keys are used for each operation. The web commonly uses asymmetric encryption during HTTPS handshakes to exchange secrets securely before switching to fast symmetric encryption for the session. Encrypted data is decrypted only with the correct key; losing keys can make data permanently inaccessible. File systems, databases, and cloud services often provide encryption at rest to protect stored data. Understanding encryption basics helps developers avoid dangerous mistakes like storing keys alongside encrypted files or transmitting secrets without protection.