JavaScript Callback Functions Explained

Callback Functions – Callbacks are functions passed as arguments to be invoked after a task completes. They're commonly used for async code like network requests or timers.

👉 Syntax

function fetchData(callback) {
  setTimeout(() => {
    callback('Data received');
  }, 1000);
}

🧪 Example

function fetchData(cb) {
  setTimeout(() => cb('Done!'), 1000);
}
fetchData((data) => console.log(data));