What is the difference between functionality and features?

From http://wiki.answers.com/Q/What_is_the_difference_between_functionality_and_features

Functionality refers to how well something works. 
Features refer to what something can do.

A Feature is a sub-system or facility that in included within a larger system.

A Function is the an action that can be performed within the system. Many Functionalities are enabled through a Feature.

For instance, User Administration is a feature offered in Windows. Add User, Grant Privilege to User, Delete User, List Users, etc. are Functions enabled by the User Administration feature.