Adding and removing elements from an array is not that difficult; however, it can be tricky. For the examples we will create in this section, let's consider that we have the following numbers array initialized with numbers from 0 to 9:
let numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
If we want to add a new element to this array (for example, the number 10), all we have to do is reference the latest free position of the array and assign a value to it:
numbers[numbers.length] = 10;
Note
In JavaScript, an array is a mutable object. We can easily add new elements to it. The object will grow dynamically as we add new elements to it. In many other languages, such as C and Java, we need to determine the size of the array, and if we need to add more elements to the array, we need to create a completely new array; we cannot simply add new elements to it as we need them.