// Array :- It is collection more the single value inside an variable // copywithin -It copies the element from the own array and return to new array // array.copyWithin(target, start, end) // target - position where the copied element take place // Start :- from which index it is gonna start the copying // end : before the specified index var arr=["AngularJS","Node.js","JQuery","Bootstrap"] // place at 0th position, the element between 1st and 2nd position. console.log(arr); var result=arr.copyWithin(0,1,2); //if we given the target as 2/3 it will not replace the element before the indexcing console.log(result); //And this methos change the original array also console.log(arr);