Percent means out of one hundred. It is often shown with the symbol "%". It is used even if there are not a hundred items. The number is then scaled so it can be compared to one hundred. Percent is also used to indicate changes in numerical quantities.
For example, we have a bowl of fruit with three apples and one orange. The percentage of apples is 3 out of 4, or 3/4 = 75/100 = 75%.