* Registration is the *process* of selecting your courses for a given semester or term. It involves logging into a student portal, choosing classes based on availability, and potentially paying fees or submitting paperwork. It's the *action* you take to sign up for classes.
* Enrollment is the *status* of being officially a student at the college for a specific term. Once you've completed the registration process (successfully added classes to your schedule) and met all other requirements (like paying tuition), you are *enrolled*. It's the *outcome* of registration.
Think of it this way: Registration is the *verb* (the action of signing up), while enrollment is the *noun* (the state of being a registered student). You register *to* become enrolled.