What is Dwarf Star? A Dwarf star is a fairly small sized star with low brightness. Many of the main sequence stars are Dwarf stars. The concept was initially invented in 1906 when the Danish astronomer Ejnar Hertzsprung discovered that two distinct classes could be separated into the reddest stars — classified as K and M in the Harvard Scheme. Either they are much lighter than the Sun, or they are much fainter. He named them “giant” and “dwarf” stars, to differentiate these classes.
What is Supernova? The Brightest Explosion In Space

The Dwarf stars are smaller and the giants are shinier than the Sun. Most stars are currently labeled using the letters O, B, A, F, G, K, and M under the Morgan Keenan System, a sequence from the hottest: O type to the coolest: M type.
What Is Active Galactic Nucleus? AGN Explained In Details

Dwarf star alone normally corresponds to any major sequence star, a V-class luminosity star: main sequence stars (dwarfs). Furthermore, the definition of the word “dwarf” was extended to use:
- Red Dwarfs: They are mainly low-mass main-sequence stars.
- Yellow Dwarfs: main-sequence star mass comparable to Sun.
- Orange Dwarfs: main-sequence K type star.
- Blue Dwarfs: They are Hypothesized grouping of very-low-mass stars increasing in temperature when they are close to the end of their main sequence life.
- White Dwarfs: They are Star consisting of electron-degenerated matter, considered to be the final stage of star formation not massive enough to crash into a neutron star or a black hole — stars less dense than around 9 solar masses
- Black Dwarfs: A white dwarf that has cooled enough to not emit any visible light any more.
- Brown Dwarfs: A substellar body not too large to fuse hydrogen into helium, but still large enough just to fuse deuterium — less than around 0.08 solar masses and more than 13 Jupiter masses.