What are JSON Web Tokens (JWT)?

A JSON Web Token (JWT) is a widely used open standard designed for securely exchanging information between two parties—typically a client and a server.

Each JWT contains encoded JSON objects that include a set of claims.

These claims represent various types of data, such as user identity, permissions, or other essential details.

Structure of a JWT

A JWT is divided into three key components:

• **Header: **Provides details about the type of token and the algorithm used for signing.
• Payload: Contains the claims, which include the data to be shared.
• Signature: Ensures the token's authenticity and guards against tampering.

Common Use Cases

1. Authentication: JWTs are frequently used for user authentication. After a successful login, the server generates a JWT, which is included in subsequent client requests.
2. Authorization: JWTs can store user roles and permissions, granting access to specific resources.
3. Single Sign-On (SSO): JWTs streamline authentication across multiple systems or applications without requiring repeated logins.

Best Practices for Using JWTs

Set an expiration time to limit the token’s lifespan.

• Always use HTTPS when transmitting JWTs to prevent interception.
• Avoid embedding sensitive data in the JWT payload, as it is visible to anyone with access to the token.

🔗 Connect with me on LinkedIn:

Let’s dive deeper into the world of software engineering together! I regularly share insights on JavaScript, TypeScript, Node.js, React, Next.js, data structures, algorithms, web development, and much more. Whether you're looking to enhance your skills or collaborate on exciting topics, I’d love to connect and grow with you.

Follow me: Nozibul Islam