What are the differences between promises and callbacks in JavaScript?

What are the differences between promises and callbacks in JavaScript?

Promises and callbacks are both used for handling asynchronous operations in JavaScript. Callbacks are functions passed as arguments to other functions, while promises represent a value that may be available now, or in the future, or never.

Can you give me an example of a callback?

Sure! Here's a simple example:

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

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

And how would that look with a promise?

Using a promise, it would look like this:

function fetchData() {
    return new Promise((resolve) => {
        setTimeout(() => {
            resolve('Data received!');
        }, 1000);
    });
}

fetchData().then((data) => {
    console.log(data);
});

What are the advantages of using promises over callbacks?

Promises provide better error handling and avoid callback hell, making the code cleaner and easier to read.