Glossary · Phase 8 · APIs

Promise

Also written: promises

A JavaScript value that stands for a result that isn't ready yet; it settles once, fulfilled with a value or rejected with an error.

A promise stands for a result that isn't ready yet. It starts pending, then becomes fulfilled with a value or rejected with an error, once, for good. fetch returns one, as does anything that waits.
From the lesson Async JavaScript: promises, await and fetch

Try it now

Step through one await. The page stays responsive in the middle, while the request is out.

Learn it properly

Async JavaScript: promises, await and fetch · The event loop, async and await, fetch with res.ok checks, Promise.all, and timeouts with AbortController. About 30 minutes.

Create a free account See what's in the lesson

Other terms from the same lesson

AbortController: A JavaScript object whose signal is passed to fetch; calling abort() cancels the request, as a Stop button does.

Never trained an AI?

Teach a small one to write, right in your browser. It takes about 20 seconds and needs no account.

Teach it to write