JWT stands for JSON Web Token. It's how modern apps handle authentication. Instead of storing user info on the server, they store it in this signed token.

What the Decoder Shows

A JWT has three parts: header, payload, and signature. The payload is where the user data lives - name, ID, role, whatever the app needs. A decoder lets you read this without validating the signature.

Super useful for debugging auth issues or understanding what an app knows about you!