See ScrumProcess for a good starting point about Scrum, including most of the former content of this page.
See ScrumOverview for a description of what goes on during Scrum.
"Scrum Methodology" may refer to the formalized version of Scrum, available from ADM (AdvancedDevelopmentMethods), which makes Scrum look like a heavyweight process.
So ScrumProcess is the thing you learn from the ScrumBook, and the thing that people usually mean when they say they're "doing Scrum." ScrumMethodology is a formal product available from ADM.
See also http://scrummethodology.com