What are "termination points" and why do I need them on my electrical supply?
The termination points are where the utility attaches their wires to your system. You need 3 termination points because most US residences have 240/120 split phase service which is provided on three wires: two hots plus a neutral. The ground is of course provided by you via ground rods or (my favorite) a Ufer Ground (concrete enclosed grounding conductor).

Here is a photo of an overhead service termination.


Click for larger view