A percentage is a way to express a number as a fraction of 100. It helps us understand how much of something there is compared to a whole. For example, if you have 25 out of 100 apples, you can say you have 25% of the apples. This makes it easier to compare different quantities, like how much of a pizza is left after sharing with friends. Percentages are commonly used in everyday life, such as in sales and discounts. If a store offers a 20% discount on a shirt that costs $50, you can calculate the savings by finding 20% of $50, which is $10. So, you would pay $40 for the shirt.