Delegate vs. delegate keyword

From http://msdn.microsoft.com/en-us/library/system.delegate.aspx:

The Delegate class is the base class
for delegate types. However, only the
system and compilers can derive
explicitly from the Delegate class or
from the MulticastDelegate class. It
is also not permissible to derive a
new type from a delegate type. The
Delegate class is not considered a
delegate type; it is a class used to
derive delegate types.

Most languages implement a delegate
keyword, and compilers for those
languages are able to derive from the
MulticastDelegate class; therefore,
users should use the delegate keyword
provided by the language.