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Javascript Manual: `Array.prototype.includes()` vs. `Array.includes()`

Incoming "noob" question:

Javascript has an includes method on arrays.

It looks like:

Array.includes()

But when I go to the Javascript Manual to understand this method, the heading on that page (for an appropriate technical reason, I realize) is: 

Array.prototype.includes()

Similar things in the Javascript Manual have caused me to not like the manual at all (and alas, I rely on W3Schools more than the manual).

However, I really really want to learn to interpret the manual.

So, my question is: what's the significance of including the word .prototype in Array.prototype.includes() in the documentation, when the actual usage looks like: Array.includes()?

(Also, if anyone has suggestions on how I can improve my comprehension of the official Javascript Manual, I'd appreciate suggestions.)

Solution

  • If the documentation said Array.includes() you would literally type it like this (example):

    Array.includes(1);

    Instead it says Array.prototype.includes() which means it isn't called on the Array type itself, but on an instance of it. So in this case you would write:

    const numbers = [1, 2, 3];
numbers.includes(1);