Asynchronous JavaScript

How does JS handle asynchronous code?

Questions to consider

1. What's the difference between "synchronous" and "asynchronous" code? Why might synchronous code be called "blocking"?

2. What are the event loop and the call stack?

3. How do callbacks and promises help us?

Useful resources

These resources are helpful extra reading that may clarify or enhance concepts you're learning in the main curriculum.

• HTTP topic intro

• How DNS Works

  A comic explaining what happens when you type a URL into your browser.

• HTTP Overview - MDN

  Describes the HTTP protocol in a lot more detail. May be useful if you like learning exactly how stuff works under-the-hood, but may also be overwhelming.

• First-class Functions

  How functions and callbacks work in JavaScript. Based on a workshop from this week's curriculum.

• Asynchronous concepts

• Introducing asynchronous JS

• What the heck is the event loop anyway? (video)