Description: Key usage in the context of cryptography refers to the application of cryptographic keys to ensure the confidentiality, integrity, and authenticity of information. These keys can be symmetric, where the same key is used for both encrypting and decrypting data, or asymmetric, which use a pair of keys: a public key and a private key. The defined purpose of a cryptographic key can include encrypting sensitive data, digitally signing documents to verify their authenticity, and creating secure connections over networks. Public Key Infrastructure (PKI) is a system that manages the creation, distribution, and revocation of digital keys, facilitating trust in electronic communications. In the realm of data loss prevention, keys play a crucial role in protecting sensitive information from unauthorized access. In data tokenization, keys are used to transform sensitive data into tokens that can be used without compromising the original information. Finally, in virtual private networks (VPNs), keys are essential for establishing secure tunnels that protect information transmitted over the Internet, ensuring user data privacy and security.