What is API?

An API, or Application Programming Interface, is a set of rules and tools that lets different software programs talk to each other. Think of it as a menu in a restaurant: the menu lists what you can order, and the kitchen (the software) prepares it for you without you needing to know how it’s cooked.

Let's break it down

  • Request: Your app sends a request to another service, asking for data or an action.
  • Endpoint: This is the specific URL or address where the request is sent.
  • Response: The service replies with the information you asked for, often in a format like JSON or XML.
  • Methods: Common actions are GET (read data), POST (create data), PUT (update data), and DELETE (remove data).

Why does it matter?

APIs let developers build powerful apps quickly by reusing existing services instead of creating everything from scratch. They enable features like login with Google, weather forecasts, payment processing, and more, making software more connected and functional.

Where is it used?

  • Mobile apps (e.g., fetching social media feeds)
  • Websites (e.g., loading product listings)
  • Smart devices (e.g., IoT sensors sending data to the cloud)
  • Business systems (e.g., linking inventory software with shipping carriers)
  • Public services (e.g., government data portals)

Good things about it

  • Speed: Faster development by leveraging existing services.
  • Scalability: Services can be upgraded independently.
  • Flexibility: Different platforms (web, mobile, desktop) can use the same API.
  • Collaboration: Teams can work on separate parts of a system without stepping on each other’s toes.

Not-so-good things

  • Dependency: If the external API changes or goes down, your app can break.
  • Security risks: Improperly secured APIs can expose data or be attacked.
  • Complexity: Managing many APIs, versioning, and documentation can become challenging.
  • Performance: Each API call adds network latency, which can slow down the user experience if not handled well.