What is the difference between Promises and Async/Await in JavaScript?

What is the difference between Promises and Async/Await in JavaScript?

Promises are objects that represent the eventual completion or failure of an asynchronous operation, while Async/Await is syntactic sugar built on top of Promises that allows for writing asynchronous code in a more synchronous manner.

Can you give me an example of how to use both?

Sure! Here's a simple example:

Using Promises:

fetch('https://api.example.com/data')
  .then(response => response.json())
  .then(data => console.log(data))
  .catch(error => console.error('Error:', error));

Using Async/Await:

async function fetchData() {
  try {
    const response = await fetch('https://api.example.com/data');
    const data = await response.json();
    console.log(data);
  } catch (error) {
    console.error('Error:', error);
  }
}
fetchData();

Which one is better to use?

It depends on the context. Async/Await often makes the code easier to read and maintain, especially with complex asynchronous flows. However, Promises can be more flexible in certain scenarios, like when you need to handle multiple asynchronous operations simultaneously.

Are there any performance differences?

In general, there are no significant performance differences between the two. Both are built on the same underlying mechanism, but Async/Await may introduce slight overhead due to its syntactic sugar. However, this is usually negligible compared to the benefits of improved readability.