What is the difference between alliance contribution & alliance score?

When you donate to the alliance technology you will earn alliance contribution points for your self and the same amount of alliance score for the alliance.

The alliance score points are used to put items into the alliance store (by R4/R5 member). the points are tied to the alliance and needed to store the store for your to buy things from.

Your alliance contribution points can then be used by you to buy the items from the store for yourself. The points are yours though and any that you have will stay with you if you change to a new alliance.