Lecture 362:- Authentication With APIs - JWT

JWT (JSON Web Token) is a standard used to create access tokens for user authentication. JWT is commonly used in web applications as a means of transferring data securely between clients and servers.

JWT consists of three parts:

1. Header: contains information about the type of token and the algorithm used to generate it.
2. Payload: contains the user information, like user id, name, email, etc., as well as other information like the token expiration date.
3. Signature: is used to verify the message hasn't been tampered with.

When a user logs in, the server generates a JWT token and sends it back to the client, which can store it in the browser's local storage or session storage. Then, every time the user sends a request to the server, the JWT token is sent with the request in the Authorization header.

On the server, the token is verified using the signature and payload information, and if the token is valid, the user is authenticated and the request is processed.

JWT authentication provides several benefits, such as scalability, security, and simplicity. Since the server doesn't need to keep track of user sessions, it can handle a large number of users more efficiently. JWT tokens can also be used to grant access to different parts of an application, and since the token contains all the necessary user information, the server doesn't need to query the database for every request.