The Array.Push() adds a new element, containing the entered variable, to the end of the array.
The Array.Pop() method on the other hand, does quite the opposite, deleting the last element of an array.
Shift works almost exactly like POP, with one major difference. It deletes the first value in an array and moves the rest backwards.
Unshift adds a new value to the start of an array instead of the end (Like the PUSH does)
It's first argument determines where to add new elements.
The Second argument is how many after that point should be deleted.
All other arguments are values you're adding.
Slice creates a new Array that contains every element from a certain point on in whatever array you give it!
Concat returns a new array with all members of the current one & adds item to it.