BMI stands for Body Mass Index. It’s a measure that relates a person’s weight to their height. It’s calculated by dividing a person’s weight in kilograms by the square of their height in meters (BMI = weight (kg) / height (m)^2).

BMI is commonly used as a screening tool to determine whether a person is underweight, normal weight, overweight, or obese. While it’s a useful indicator for most people, it’s important to note that BMI doesn’t directly measure body fat. Therefore, it may not be accurate for athletes, pregnant women, elderly individuals, or individuals with a high muscle mass.