Outcomes, Competencies, and Goals are all terms for the same thing in Moodle. Once Outcomes are enabled site-wide and within a course, you can set up an activity which has one or more Outcomes associated with it and each of these Outcomes can have a grade associated with it. Normally, grades for Outcomes are created using a custom scale other than numbers.

However, unlike a normal grade, you can allocate an Outcome to a number of activities. This makes it quite powerful for use within building competency maps. So, when you grade an activity, you not only provide an overall grade for the activity, but also for the Outcome. Hence, someone could pass a test but display a less than desired level for the Outcome. More on this later.