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So what's an iterable in Javascript? An iterable can be defined

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technically, there it's basically an object or any objects that implement the iterable protocol and have

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to is @@iterator method with the symbol iterator property.

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Now symbols are a special type of values in Javascript, we'll dive into them way later since they're really

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niche and specific and therefore the human readable definition of an iterable in the end is that we can use a for/of

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loop on it.

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Yes, it's indeed as simple as that,

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we can loop through it with for/of.

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Now the important thing is that not every iterable in Javascript is an array.

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We work with arrays thus far but there also are other iterable objects, like a node list for example

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which we saw in the last course module

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but also strings and also maps and sets which we'll have a look at later.

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Now there also is another term which I already used and that's array-like and that's actually not the

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same as an iterable,

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both iterable and array-like are official terms in the Javascript language.

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Now what are array-like objects therefore?

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Again, the technical definition is here, much more readable, that an array-like object are in the end any

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objects that have a length property and use indexes to access items,

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it's as simple as that

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and I'd say it is also pretty clear to us humans. Now just as with iterables, not every array-like object

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is an array,

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that's why it's called array-like. We have array-like objects, like node list and string. Node lists and

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strings are objects that have a length, that have indexes and where we can use for/of and still, they're

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not real arrays because as you will learn in this module, real arrays have a couple of interesting behaviors

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and also a bunch of important methods available to them which do not exist on these array-like or

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iterable objects.

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Now with these definitions out of the way, let's dive a bit deeper into arrays before we then also have

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a look at other array-like objects and iterables.