To use APIs in your projects, you typically interact with them through JavaScript. Modern browsers expose a wide range of APIs, such as Geolocation, Clipboard, and Fullscreen, directly on global objects like window, navigator, or document. Before using any API, you should check if it is available in the user's browser—a process called feature detection. This helps you avoid errors in browsers that do not support a specific API.

Feature detection is simple: you check if a property or method exists before calling it. This practice improves your code's compatibility and ensures a smoother experience for users across different browsers and devices. Always remember to provide fallback behavior or user feedback when an API is not available. Keeping your code resilient and user-friendly is a key part of working with APIs.

Here is a minimal example showing how to detect if the Geolocation API is supported in the user's browser. If it is, you can safely use it; if not, you can display a helpful message to the user.