Final answer:
Body mass index (BMI) is a measure of body weight in relation to height. It helps estimate the fat content of the body and classify individuals into different weight categories. Calculation involves dividing weight by the square of height.
Step-by-step explanation:
Body mass index (BMI) is a measure of body weight in relation to height. It is calculated by dividing a person's weight (in kilograms) by the square of their height (in meters). BMI is used to estimate the fat content of the body and classify individuals as underweight, normal weight, overweight, or obese. For example, a BMI value between 18.5 and 24.9 is considered normal weight, while a BMI over 30 is classified as obese.