NDVI False Color measures greenness of the vegetation. It measures the difference between the Red and Near Infrared bands.
Lyr 451 depicts healthy vegetation in shades of reds, browns, oranges and yellows. Opened, developed areas appear in shades of white and near white colors. Adding mid infrared band allows for detection of stages of plant growth or stress.
Supervised Classification allows us to assign certain pixel values to specific objects. In turn, ArcMap extrapolates those values to the entire image.