What if you want to delete an element from Array ??
Mostly people use delete command but it leaves undefined behind it
>>> var list = [1,2,3];
>>> delete list[1];
>>> list
[1, undefined, 3]
Now try splice instead of delete
>>> var list = [1,2,3];
>>> list.splice(1, 1); // Remove one element, returns the removed ones.
[5]
>>> list[4, 6]
And it's done...