# Async, Await use over Promise with examples.

The objective of this blog is to summarize the understanding of Async function and some brownie points of using it compared to Promises.

## What is Async and Await ?

Async and Await are keywords(in JS) which are used to give asynchronous(i.e promise-based behavior ) powers to a function if a function is declared in format below:-

```plaintext
async function getLikes() {
  const result = await getPostLikes();
  console.log(result);
  // expected output: "resolved"
}
```

Let's understand the above code snippet,

1. getLikes is a async function name ,as it getLikes is declared with \*async \* keyword .
    

2.Function body containing *await* mechanism.

3.Function (getLikes here) always return a promise(if not explicitly then implicitly).

## Understanding how Await is used here

* Async functions can contain zero or more await expressions.
    
* Await when used in async function suspend execution until the returned promise is fulfilled or rejected, and this way mimic the synchronous behavior.
    
* The use of await keyword is only valid inside async functions within regular JavaScript code.
    

## Advantages of using it over directly using Promises are:-

* To simple and more intuitive syntax necessary to consume promise-based APIs.
    
* It enables us to use try / catch blocks around asynchronous code.
    
* Avoid .then hell
    

## .then hell ?

Let's understand how we will write same function first with using Promise then with Async and Await.

![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1644407305462/cwqiCRSm7.png align="left")

![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1644406798816/IQOrsr11H.png align="left")

With Async Await code it is fairly easy to to read and understand what's the function is trying to acheive.