By recent estimates, two-thirds of the people in the United States are overweight and about half of those are obese. This causes significant increases in illnesses such as diabetes and heart disease. To determine whether a person is overweight or obese, you can use a measure called the body mass index (BMI). The United States Department of Healthand Human Services provides a BMI calculator at http://www.nhlbi.nih.gov/guidelines/  obesity/BMI/bmicalc.htm. Use it to calculate your own BMI. An exercise in Chapter 3 will ask you to program your own BMI calculator. To prepare for this, research the formulas for calculating BMI.