API

Definition

An API (Application Programming Interface) is a set of rules, protocols, and tools that enables different software applications to communicate with each other. APIs define how requests are made, what data formats are used, and what responses are returned.

Simple Explanation

Think of an API as a restaurant menu. The menu tells you what you can order (available endpoints), what information you need to provide (parameters), and what you'll get back (response format). You don't need to know how the kitchen works — you just follow the menu and wait for your order.

Real-World Use Case

When building a web app that displays weather data, you call a weather API. The API handles all the complexity of sensor networks and forecasts, and returns structured data you can display.

Examples

Related Terms

Learn More

• MDN Web Docs — APIs
• OpenAPI Specification