Note: You are currently viewing documentation for Moodle 3.3. Up-to-date documentation for the latest stable version of Moodle is probably available here: login/index.
The editing login/index provides the user full or partial access into the Learning Management System.
Each individual course may also have a one-time "enrolment key". To take a course that requires an enrolment key, a registered user will need that key from the instructor.