Cryptography is the practice of securing information by transforming it into a format that is unreadable to unauthorized users. This process involves using algorithms and keys to encrypt and decrypt data, ensuring that only those with the correct key can access the original information. It is widely used in various applications, including online banking, messaging apps, and secure communications. The field of cryptography encompasses various techniques, such as symmetric encryption, where the same key is used for both encryption and decryption, and asymmetric encryption, which uses a pair of keys. Cryptography plays a crucial role in maintaining privacy and security in the digital age.