JavaScript Promises

Learn JavaScript Promises

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Knowledge Check

Take this customized & interactive quiz to test your knowledge on JavaScript Promises, then check out the learning resources below.

Question 1 of 7

What is an object that represents the eventual completion or failure of an asynchronous operation?


Core Learning

The fastest way to learn JavaScript Promises is simply to study these exact resources. Focus on the 👀 to learn extra quickly and save time!

What is asynchronous programming?

👀 1 Thing to Focus On

  • Before we dive into promises, let's first learn what it means for something to be asynchronous.

What is a Promise?

👀 2 Things to Focus On

  • Just worry about the definition for now, we'll cover other bits later.
  • Do understand the different states that a Promise goes through.

How to use a Promise

👀 1 Thing to Focus On

  • Understand how to wait for the value of a Promise, and what to do if there is an error.

Promise.finally()

👀 1 Thing to Focus On

  • What happens if you need a bit of logic to fire regardless of the result of the Promise, but you do need to run after the Promise returns?

Promise.all()

👀 1 Thing to Focus On

  • What should you do if you need multiple promises?

Promise.race()

👀 1 Thing to Focus On

  • What should you do if you need to fire off multiple Promises, but you don't care about all of them?