Array unshift() Method

The Array unshift() method adds one or more elements to the beginning of an array and returns the length of the new array. The syntax for this method is

			array.unshift(element1, element2, ..., elementN); 
			

We consider an array named os consisting of four elements

			var os = ["Debian", "Fedora", "openSUSE", "Ubuntu"];
			

Using the unshift() method, we will add the element CentOS to the beginning of the array and assign the returned length of the new array to the variable length

			var length = os.unshift("CentOS");
			

The new modified array with one new element at its beginning becomes

			["CentOS", "Debian", "Fedora", "openSUSE", "Ubuntu"];
			

and the variable length holds the length of the new array, which is 5.