An API (Application Programming Interface) is how one program asks another for data or actions over HTTP. You send a request (a method, a URL, headers, maybe a body); the server sends back a response (a status code and usually JSON). Everything in this course is a variation on that single exchange.
The four parts of every request
- Method — GET (read), POST (create), PUT/PATCH (update), DELETE (remove).
- URL — which resource, plus a query string for options (?page=2).
- Headers — metadata: who you are (Authorization), what you send (Content-Type).
- Body — the payload for POST/PUT (usually JSON).
Credentials: the thing most people misunderstand
Real portals (Stripe, GitHub, Razorpay, Zerodha) all follow the same pattern: you register an "app" and receive an App ID (public, identifies you) and an App Secret (private, proves it is you). The secret is shown once — copy it immediately, because the server only stores a hash and can never show it again.
Create your app on the Dashboard. You will get an App ID, App Secret, an API key, and a bearer token — the raw materials for every authentication lesson.
Tip · This is a training sandbox. Never put real production credentials here — build the habit of treating secrets carefully from day one.