Cryptography

Cryptography is the practice of secure communication in the presence of third parties. It involves the use of mathematical algorithms and protocols to protect the confidentiality, integrity, and authenticity of information. Cryptography is used in a variety of fields, including computer science, engineering, and political science, and it has a number of important applications, including secure communication, data protection, and online transactions.

There are two main branches of cryptography: symmetric-key cryptography and public-key cryptography. In symmetric-key cryptography, the same key is used to encrypt and decrypt the message. This means that both the sender and the recipient of the message must have a copy of the key in order to communicate securely. In public-key cryptography, on the other hand, each user has a pair of keys: a public key and a private key. The public key is used to encrypt the message, and the private key is used to decrypt it. This allows for secure communication without the need for the sender and recipient to share a key.

Cryptography is an essential tool for protecting information in the digital age, and it plays a vital role in the security of online communications, financial transactions, and other sensitive data.