Cryptography is the practice of securing information by transforming it into a form that is unintelligible to anyone who does not have the proper key or password to decode it. It involves techniques for encrypting and decrypting data to protect it from unauthorized access or modification.
Cryptography has been used throughout history to protect sensitive information such as military secrets, diplomatic messages, and financial transactions. It is now widely used in computer networks to ensure the security of data transmitted over the Internet, such as passwords, credit card numbers, and other confidential information.
Modern cryptography relies on algorithms and protocols that are designed to be mathematically secure and resistant to attacks by hackers or other malicious actors. Common cryptographic techniques include symmetric-key encryption, public-key encryption, digital signatures, and hash functions.
(Ed: written by ChatGPT; verified by jrivett.)