What are the differences between Promises and Callbacks in Node.js?

What are the differences between Promises and Callbacks in Node.js?

Promises are objects that represent the eventual completion or failure of an asynchronous operation, while callbacks are functions passed as arguments to be executed after a task is completed.

Can you give me an example of using a callback in Node.js?

Sure! Here's a simple example:

fs.readFile('file.txt', (err, data) => {
  if (err) throw err;
  console.log(data);
});

In this case, readFile takes a callback that handles the result.

How would that look using Promises instead?

Using Promises, it would look like this:

fs.promises.readFile('file.txt')
  .then(data => console.log(data))
  .catch(err => console.error(err));

This way, you can chain multiple operations more easily.

Which one is better to use?

It depends on the situation. Promises provide better error handling and can be easier to read, especially with async/await syntax, while callbacks can be simpler for straightforward tasks.