Quantum cryptography refers to the use of quantum mechanics principles to secure communication and protect sensitive information from unauthorized access. It leverages the behavior of subatomic particles, such as photons, to create cryptographic keys with unprecedented security features. One notable aspect is the concept of quantum key distribution (QKD), which allows two parties to share a key securely, ensuring that any attempt at eavesdropping is detectable. This makes quantum cryptography fundamentally more secure than classical methods, as it relies on the laws of physics rather than complex mathematical algorithms. Its potential applications are significant for securing data transmission in various fields, including finance and national security.