Compare Promise.all, Promise.allSettled, Promise.race and Promise.any.

All four take an iterable (for example an array) of promises and return one promise. They differ in when that promise settles.

Promise.all:

• It fulfills when all promises fulfill. The result is an array of values in the same order as the input.
• It rejects as soon as any one rejects. This is called fail-fast.
• The other promises keep running. Their results are just ignored.
• Use it when you need every result.

Promise.allSettled:

• It never rejects. It waits for all promises to finish.
• It gives an array of { status: 'fulfilled', value } or { status: 'rejected', reason } objects.
• Use it when some failures are acceptable.

Promise.race:

• It settles the same way as the first promise to settle, whether that one fulfilled or rejected.
• A common use is a timeout: race the request against a timer.

Promise.any:

• It fulfills with the first promise that fulfills, and ignores rejections.
• It rejects only if all promises reject, with an AggregateError.
• Use it to try several sources for the same data.

None of them cancel the promises that are still running.