What is the difference between an iterator and a generator, and when would you use one over The other?

Answer 1

You can visit :

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Iterators_and_Generators

Answer 2

In essence, Ive learnt that the difference between n iterator and a generator, is:

that the generator is simply a function with * affixed.
it uses the yield keyword to iterate over its members.
it can also call other generators with *
you can control it manually with the .next() method.

the iterator is created with [Symbol.iterator]()
it can also be iterated over with the next().value methods

iterators and generators are useful in asynchronous programming