APIs & Data Fetching
intermediateTopic 9 of 14 in Frontend Development
What it is
An API (Application Programming Interface) is a way for your frontend to talk to a server and exchange data. Data fetching is the process of sending requests to an API and using the response to update your UI.
Why frontend developers need it
Almost every modern web app loads data from a server — user profiles, product lists, search results. Knowing how to fetch, display, and handle errors from APIs is essential for building real applications.
What to learn
HTTP methods: GET, POST, PUT, DELETE
The fetch API and response handling
JSON: parsing and stringifying data
Query parameters and headers
Loading, error, and empty states in UI
CORS and how it affects frontend requests
REST API conventions
Introduction to GraphQL (optional)
Practice project
Weather Dashboard
Build an app that fetches weather data from a public API (like OpenWeatherMap). Show current conditions, a five-day forecast, and let users search by city. Handle loading and error states gracefully.