“Unlike in other parts of the world, it is both customary and expected for customers to tip the servers when going out to restaurants, bars, and coffee shops in America. At most places, servers don't get paid usual wages. Rather, they take home their daily tips as a salary. The average tip that each customer must pay is about 20% of the bill, depending on the service and on the quality of the restaurant. If paying with a credit card, the customer writes the tip in the space below the cost of the meal and then adds it into the total payment. If paying in cash, the customer first pays the server the price of the meal and then leaves the tip on the table before exiting the restaurant.”