← REST API Development learning pathREST API Development · Module 1 of 10
What is an API?
An API lets programs talk to each other; REST is the most common style on the web.
📖 Key ideas
- API = Application Programming Interface: a contract between programs.
- Web APIs exchange data over HTTP, usually as JSON.
- REST organises an API around resources like /users and /orders.
- Clients (apps, websites) send requests; servers send responses.
- Examples: payment APIs, weather APIs, maps APIs.
💡 Real-life example: An API is a restaurant menu: you order by name and the kitchen sends the dish without showing you how it is cooked.
APIContract for programs to communicate
RESTResource-based web API style
ResourceA thing exposed by the API, like a user
JSONCommon data format for APIs