With the new LINQ to XML API comes a new object model containing many new classes that exist in the System.Xml.Linq namespace. One is the static class where the LINQ to XML extension methods live, Extensions; two are comparer classes, XNodeDocumentOrderComparer and XNodeEqualityComparer, and the remaining are used to build your XML trees. Those remaining classes are displayed in the diagram shown in Figure 7-1.
There are some interesting things to notice:
Of those remaining classes, three are abstract, XObject, XContainer, and XNode, so you will never be constructing them.
An attribute, ...