The Normalized Difference Vegetation Index (NDVI) is a numerical indicator used to assess the health and density of vegetation. It is calculated using satellite imagery, comparing the difference between near-infrared light, which vegetation strongly reflects, and red light, which vegetation absorbs. The resulting value ranges from -1 to +1, where higher values indicate healthier and denser vegetation. NDVI is widely used in fields such as agriculture, forestry, and environmental monitoring. By analyzing NDVI data over time, researchers can track changes in plant health, assess drought conditions, and manage natural resources more effectively.