For example, students buy food, clothing, notebooks, paper, automobile insurance, and movies at the theater. In order to pay for the goods and services they buy, students use income they earn babysitting, working at fast-food restaurants, or other jobs. They might also use part of their parents' income.
Businesses produce goods and services to sell in the product markets.
There are many, many businesses providing a wide variety of goods and services that students buy. When a student buys a new pair of jeans, he or she pays the store from which the jeans were purchased. This payment is revenue for the store. When students work, they provide labor in factor markets. In exchange for work, they expect to receive payment in the form of wages or salaries.