## Spread Operator The spread operator expands an array or places the contents of one array into another array: ```js const middle = ['lettuce', 'cheese', 'patty']; const burger = ['top bun', ...middle, 'bottom bun']; console.log(burger); // ['top bun', 'lettuce', 'cheese', 'patty', 'bottom bun']; ``` The spread operator only works in-place, like in an argument to a function or in an array literal. The following code will not work: ```js const spreaded = ...arr; ``` [see](https://teamtreehouse.com/library/javascript-objects-2/loop-through-objects/useful-javascript-object-methods)