Elements

All of the elements in the document hierarchy have the following useful attribute:

• element.childNodes - a read-only array containing the children of element. The size of this array is element.childNodes.length. Although the array is read-only, it can be manipulated using methods described below.

All of the elements in the document hierarchy have the following useful methods:

• getElementsByTagName(tagName) - returns an array of HTML elements whose tag name is tagName. The entire descendent hierarchy is searched.
• appendChild(element) - appends element at the end of the childNodes array.
• removeChild(child) - removes child from the childNodes array.
• replaceChild(newChild, oldChild) - replaces oldChild in the childNodes array by newChild.

Nodes are not created by invoking constructors. They are created by invoking the Document methods createTextNode() and createElement().