JWT (JSON Web Token)

Definition

JWT is an open standard (RFC 7519) that defines a compact and self-contained way to securely transmit information as a JSON object. A JWT consists of three parts: Header (algorithm and token type), Payload (claims data), and Signature (verification hash), encoded as Base64URL segments separated by dots. JWTs are commonly used for authentication (stateless sessions), authorization (access control), and information exchange. The signature ensures the token has not been tampered with.