When we raise something to a power, it really justs means we are multiplying it by itself. 3^2 (3 to the power of 2) means that we are mutliplying 3 by itself: 3•3 = 9 or 3^2 = 9 (there are two 3's)
However, when we rasie something to the 0 power, it equals 1. That is because we are multiplying it by itself 0 times. We are not multiplying it by zero, we are effectively doing nothing at all. 3^0 = 1