S-box

An S-box, or substitution box, is a fundamental component used in symmetric key cryptographic algorithms, particularly in block ciphers. Its primary role is to provide non-linearity in the encryption process, which helps secure the algorithm against various attacks, including linear and differential cryptanalysis. Here's how S-boxes work: 1. **Input and Output**: An S-box takes an input value (usually a binary string of fixed length) and substitutes it with a corresponding output value.