How does someone have a credit score, but no credit history to speak of(as far as I know)?? Cayman for your time.

So at one point this summer, I applied for a loan, knowing that I had no credit, or history to speak of. Of course, I was rejected said loan because of an insufficient history via form letter from the credit union I applied at; but it said I had a credit score(I will not disclose the number though). Where'd this number come from??