Example

var owner = node.ownerDocument;

In the example above, if node is an Element then the owner variable will be a reference to the document that contains it.

The owner document reference can then be used to call methods of Document, as in the following example:

var owner = node.ownerDocument;

var em = owner.createElement('em');

em.appendChild(owner.createTextNode('Exterminate!'));

node.appendChild(em);