Welcome to the Treehouse Community
Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.
Looking to learn something new?
Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.
Start your free trialRushabha Jain
Full Stack JavaScript Techdegree Student 11,141 PointsPromise.all()?
Whether promises are executed parallely/sequentially?
1 Answer
Brendan Whiting
Front End Web Development Techdegree Graduate 84,738 PointsJavaScript is single threaded, so only one thing is happening at a time. But, we can still have concurrency. We can send off an http request and move on to something else while we're waiting for the response. When you use Promise.all()
, you fire off an array of promises, so you can have multiple requests in flight at the same time, and that could have the effect of having work done on different servers at the same time. But as far as your JavaScript program itself, it's not parallel but it can use concurrency which is usually what we're aiming for here.