Look at the graph of the nearest stars and circle the sun.
Astronomers sample part of the sky to count the number of stars in the whole sky.
Similarly we could sample the nearest stars and speculate on the characteristics of the most common stars in the galaxy. These are the stars astronomers speculate to inhabit most of the galaxy. In the combined graph you can see a heavy concentration of stars running from the lower right to upper left corner of the graph. This is the main sequence where stars begin their life as a dwarf star. The cluster of points above this line towards the upper right corner is the giant stars.