From MSDN (http://msdn.microsoft.com/en-us/library/bfz783fz.aspx):
"By convention, all attribute names end with Attribute. However, several languages that target the runtime, such as Visual Basic and C#, do not require you to specify the full name of an attribute. For example, if you want to initialize System..::.ObsoleteAttribute, you only need to reference it as Obsolete."