Just about everyone has wondered: "How does this button work?" They may not have been thinking of the world of dynamic geometry, but Chris Sangwin of the University of Birmingham has been thinking about just this subject. He recently contributed an interactive learning resource to the Journal of Online Mathematics and its Applications, and his work will no doubt command the attention of mathematics educators. Along with providing details about this nuance of dynamic geometry, the article contains several interactive applets and two short video clips. The article also contains contact information for Sangwin, so users can contact him with any queries.