Body Mass Index (BMI) is a numerical value calculated from a person’s weight and height. It serves as an important screening tool to categorize individuals into weight classifications: underweight, normal, overweight, or obese. While BMI provides a quick estimate of body fat and potential health risks, it does not account for factors like muscle mass and body composition. Therefore, it should be interpreted with caution and considered alongside other health assessments for a comprehensive understanding of a person's health status.