A dwarf star is a small and relatively low-mass star that has completed its main sequence phase of stellar evolution. These stars can be classified into different types, including red dwarfs, white dwarfs, and brown dwarfs. Dwarf stars are typically less luminous than larger stars and can have varying temperatures and sizes. Red dwarfs are the most common type of dwarf star, known for their long lifespans and low energy output. In contrast, white dwarfs are the remnants of stars that have exhausted their nuclear fuel, while brown dwarfs are substellar objects that never achieved the necessary mass to sustain hydrogen fusion.