Cryptography is the science of securing communication and information through the use of mathematical techniques, ensuring that data is accessible only to those for whom it is intended. It plays a critical role in modern digital security, protecting sensitive information such as financial transactions, personal data, and communications from unauthorized access or tampering. Cryptography encompasses various methods, including encryption, where data is transformed into a coded format that can only be deciphered with the correct key, and digital signatures, which verify the authenticity and integrity of messages. As technology advances, cryptography continues to evolve, becoming increasingly sophisticated to counter emerging threats and protect the privacy and security of information in our interconnected world.