Answer:
The Hertzsprung-Russell (H-R) diagram is a graph that plots stars according to their luminosity and temperature. To read the H-R diagram, you need to know that:
- The higher a star is, the brighter it is
- The closer to the left, the hotter the star is
- The HR diagram is divided into star types, which are (from left) O,B,A,F,G,K, and M
- The main sequence stretching from the upper left (hot, luminous stars) to the bottom right (cool, faint stars) dominates the HR diagram