In XML, 'attributes' are the "inline" properties of an 'element', like . Each 'element' may also contain its own child elements, like . An element is defined by both its attributes, and by any 'child elements' it may have. The intent for this reference is to document all of the actual complex properties, like or , for major elements that are not regular attributes. These along with attributes, make up the definition of a major XML Ui elements like widgets.