JWT
A digital ID card your app uses to remember you're logged in.
What is JWT?
JWT (JSON Web Token) is a small encrypted token stored in your browser. After you log in, your app gives you a JWT. Every request you make includes it so the server knows who you are without asking you to log in again.
Think of a JWT like a wristband at a concert. After the bouncer checks your ticket once, the wristband lets you come and go without being checked again.
In Vibe Coding
Supabase uses JWTs automatically. When a user logs in, Supabase generates a JWT and stores it in the browser. Every time your app calls Supabase, that JWT is sent along to prove who the user is.
Example
For example: You log into an app at 9am. The app stores a JWT in your browser. When you come back at 2pm, the JWT is still there — so you're still logged in without re-entering your password.
Why this matters
This matters because JWT appears repeatedly when building, deploying, debugging, or connecting services in vibe coding workflows.
When you'll hit this in practice
You will usually run into JWT when working on Security Checker.