What are asynchronous callbacks in JavaScript?

What are asynchronous callbacks in JavaScript?

Asynchronous callbacks are functions that are executed after a certain task is completed, allowing other code to run in the meantime.

Can you give me an example of how to use a callback in JavaScript?

Sure! Here's a simple example:

function fetchData(callback) {
    setTimeout(() => {
        const data = 'Data fetched!';
        callback(data);
    }, 2000);
}

fetchData((result) => {
    console.log(result);
});

In this example, fetchData simulates a data fetch and calls the provided callback with the result after 2 seconds.

What happens if I don't use a callback?

If you don't use a callback, the code that depends on the result of the asynchronous operation may execute before the operation is complete, leading to errors or unexpected behavior.