Programming Microsoft® Visual C#® 2008: The Language

System.Object

System.Object is the ubiquitous base type. All classes and structures inherit from System.Object, either directly or indirectly. System.Object encompasses the baseline behavior of all managed types. Reference types without an explicit base class inherit from System.Object implicitly. Reference types that explicitly inherit from another type still inherit from System.Object, but indirectly. You can inherit from System.Object explicitly. However, that is somewhat redundant and therefore is not often seen. Value types inherit from System.ValueType, which in turn inherits from System.Object. System.ValueType overrides System.Object members to implement the semantics of a value type.

The members of the System.Object class are explained ...