JavaScript promises helps us to handle asynchronous operations more efficiently by assigning the handler with the success value or failure reason.

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JS promises

promises

Promises are used to deal with event handling and callbacks in asynchronous programming in JavaScript, such as clicks and key presses. Promises allow developers to specify a function to execute at some later point in response to certain events. Promises may also indicate whether a certain code succeeded or failed in performing its assigned job.

In this course, you will learn how to chain different promises, which makes the code easier to understand and debug. Next, you’ll learn built-in methods to monitor and respond to multiple promises executing in parallel. Then, you will cover async functions and await expressions that are often used with promises. Finally, you’ll learn how to track promises when they are rejected without a rejection handler.

Promises are important to understand and debug the code in asynchronous programming. The concepts of JS promises help developers working with Node.js and Deno for event handling and with asynchronous JavaScript APIs.

JavaScript Promises

JavaScript promises were designed to be a low-level utility that could be used behind the scenes by higher-level language features. **Async functions** are such higher-level language features that make programming with promises more similar to programming without promises. Instead of worrying about tracking promises and their various handlers, async functions abstract away the promises. The end result is code that follows a familiar top-down sequence.
Before getting into the details of how async functions work, it helps to understand how they are defined.

## Defining async functions

Async functions can be used anywhere synchronous functions can be used. In most cases, all we need to do is add the `async` keyword before any function or method definition to make it asynchronous.   

Here are some examples:


JavaScript promises were designed to be a low-level utility that could be used behind the scenes by higher-level language features. **Async functions** are such higher-level language features that make programming with promises more similar to programming without promises. Instead of worrying about tracking promises and their various handlers, async functions abstract away the promises. The end result is code that follows a familiar top-down sequence.
Before getting into the details of how async functions work, it helps to understand how they are defined.

# Defining async functions

Async functions can be used anywhere synchronous functions can be used. In most cases, all we need to do is add the `async` keyword before any function or method definition to make it asynchronous.   

Here are some examples:


Get to know about async functions in JavaScript.

Introduction

Basics of Promises

Chaining Promises

Working with Multiple Promises

Async Functions and Await Expressions

Tracking Down the Unhandled Rejections

Conclusion

Async Functions

Defining async functions