What is the Trinity? (and why is it important?)

Michelangelo's depiction of God
Michelangelo’s depiction of God

A tortoise was making his way across the lawn when all of a sudden he was nastily mugged by a ruthless gang of snails.  Later, when the tortoise reported the crime at the police station, the officer asked him if he could describe any of his attackers.  The tortoise replied, “Oh officer, it all happened so fast!” You see it all boils down to perspective!  And more than anything else we need a right perspective or doctrine of God.