what is encryption

Encryption is the process of converting clear, readable data into a scrambled format that only someone with the correct key can reverse. At its core are algorithms that mix, substitute, and permute bits according to precise mathematical rules. Picture a 128-bit block cipher such as AES-256 as a 16×16 grid where each round applies substitution boxes and linear transformations, shuffling the grid’s tiles until the original pattern has been completely obscured. Without the secret key, the scrambled grid remains a meaningless mosaic. This digital lock-and-key mechanism protects everything from private messages and financial transactions to stored documents, serving as the invisible shield that keeps our online world secure.