What is an API?

You interact with APIs every day, often without realizing it. An API (Application Programming Interface) lets different software programs talk to each other and share data or features. Understanding APIs is the first step to building powerful, connected applications.

An API, or Application Programming Interface, is a set of rules and tools that allows different software programs to communicate with each other. You can think of an API as a messenger that carries requests and responses between different systems. When you use an app on your phone to check the weather, that app uses an API to ask a remote server for the latest weather data. The server responds with the information, and the app displays it for you. APIs make it possible for different programs, websites, or devices to work together, even if they are built by different people or companies. By clearly defining how requests for information should be made and how responses should be structured, APIs help developers create software that is reliable, efficient, and easy to connect with other services. Understanding APIs is important because they are everywhere in modern technology, powering everything from social media apps to online shopping and smart home devices.

Example: Checking Weather with an API

Imagine you are building a weather app on your phone. Your app does not store any weather data itself. Instead, it needs to know the current weather in your city.

To get this information, your app sends a request to a weather service's API. The API receives your request, checks its database for the latest weather, and sends the data back to your app. Your app then displays the temperature and forecast to you.

This process allows your app to provide up-to-date weather information without collecting or storing any weather data itself. The API acts as the messenger between your app and the weather service.