Final answer:
On the H-R diagram, stars on the main sequence are characterized by their temperature and luminosity, which are determined by their mass. Giants, supergiants, and white dwarfs are other types of stars found on the diagram.
Step-by-step explanation:
On the Hertzsprung-Russell (H-R) diagram, the main sequence is a diagonal band extending from high temperature and high luminosity to low temperature and low luminosity. Most stars are located on the main sequence and their position is determined by their mass. High-mass stars are hotter and emit more energy than low-mass stars on the main sequence. These stars derive their energy from the fusion of protons to helium. Giants and supergiants are stars that no longer lie on the main sequence as they have altered luminosity and surface temperature due to changes in their energy source, chemical composition, and interior structure. White dwarfs are another type of star found on the H-R diagram, but they form a small fraction of the total stars.