The Body Mass Index (BMI) is a numerical value derived from an individual's weight and height, providing a simple method to categorize body weight status. It is calculated using the formula: weight in kilograms divided by the square of height in meters (kg/m²). BMI is commonly used as a screening tool to assess whether individuals fall into categories such as underweight, normal weight, overweight, or obese. However, it’s important to note that BMI does not directly measure body fat and may not accurately reflect the health of all individuals.