Core difference Program indicators

Hi all,

I came across the following information that is causing confusion:
V{event_count}: Count of events

V{enrollment_count}: Count of enrollments is a subset of the Count of events

V{tei_count}: Count of tracked entity instances is counting a subset of the Count of enrollments

What does the use of enrollment_count, tei_count and event_count produce as results in the program indicators? I would like to try, if possible, a practical example in a demo. Geeting to understand the core difference is crucial for me.

Analytics Type: Event
Aggregation Type: Count
Expression: V{event_count}

Analytics Type: Event
Aggregation Type: Count
Expression: V{enrollment_count}

Analytics Type: Event
Aggregation Type: Count
Expression: V{tei_count}

Thanks