Let’s learn about some built-in JavaScript methods that make working with arrays easier. These methods are specifically called on arrays to make common tasks, like adding and removing elements, more straightforward.

One method, .push(), allows us to add items to the end of an array. Here is an example of how this is used:

const itemTracker = ['item 0', 'item 1', 'item 2'];

itemTracker.push('item 3', 'item 4');

console.log(itemTracker); 
// Output: ['item 0', 'item 1', 'item 2', 'item 3', 'item 4'];

So, how does .push() work?

• We access the push method by using dot notation, connecting push to itemTracker with a period.
• Then we call it like a function. That’s because .push() is a function and one that JavaScript allows us to use right on an array.
• .push() can take a single argument or multiple arguments separated by commas. In this case, we’re adding two elements: 'item 3' and 'item 4' to itemTracker.
• Notice that .push() changes, or mutates, itemTracker. You might also see .push() referred to as a destructive array method since it changes the initial array.

If you’re looking for a method that will mutate an array by adding elements to it, then .push() is the method for you!