The largest object is on the left, followed by a period, then the next largest object, a period, until we reach the object we want. The object on the right side of a period is a property of the larger object on the left.
Document is the current page displayed in the window and is a property of window.
It can be changed. The first object on the left doesn't always have to be the largest. As long as the object on the right is not a property of two or more objects on the left, JavaScript will know what we are attempting to reference. All rights reserved.