What is restful?

RESTful (Representational State Transfer) is a style of building web services that lets different computer systems talk to each other over the internet using simple, standard operations like GET, POST, PUT, and DELETE. Think of it as a set of rules for how to request and send data between a client (like a web browser or mobile app) and a server.

Let's break it down

  • Resources: Anything you can name (users, photos, orders) is a resource. Each resource gets its own unique URL (e.g., /users/123).
  • HTTP Methods: The actions you can perform on a resource are expressed with HTTP verbs:
  • GET → retrieve data
  • POST → create new data
  • PUT → update existing data
  • DELETE → remove data
  • Stateless: Every request from client to server must contain all the information needed; the server doesn’t keep track of previous requests.
  • Representation: Data is sent in a common format like JSON or XML, so both sides understand it.

Why does it matter?

RESTful APIs are easy to understand and use because they rely on the familiar web protocol (HTTP). This simplicity speeds up development, makes it easier for different programs to work together, and allows services to scale well since the server doesn’t need to remember past interactions.

Where is it used?

  • Mobile apps talking to back‑end servers (e.g., Instagram fetching photos)
  • Web applications loading data without reloading the page (single‑page apps)
  • Cloud services exposing functionality (AWS, Google Cloud)
  • Internet of Things devices sending sensor data to a central hub
  • Public APIs like Twitter, GitHub, and Spotify that let developers build on top of them.

Good things about it

  • Simplicity: Uses standard HTTP verbs and URLs, easy to learn.
  • Scalability: Statelessness lets servers handle many requests without heavy memory use.
  • Flexibility: Works with any data format (JSON, XML, etc.) and any client type.
  • Cache‑friendly: GET requests can be cached, improving performance.
  • Wide adoption: Lots of tools, libraries, and documentation already exist.

Not-so-good things

  • Limited to CRUD: Complex operations may feel forced into simple GET/POST/PUT/DELETE patterns.
  • Over‑reliance on HTTP: Not ideal for real‑time or bidirectional communication (WebSockets are better there).
  • Versioning headaches: Changing an API can break existing clients if not managed carefully.
  • Statelessness can be inefficient: Re‑sending the same authentication data with every request can add overhead.
  • No strict standard: While the principles are clear, implementations can vary, leading to inconsistencies.