Red dwarfs are small cool stars that usually have less than 10 per cent the mass of the Sun with surface temperatures ranging between about 2,500K and 4,000K. Although they are the most common type of star in the Universe they are intrinsically faint and not a single red dwarf is visible to the naked eye from Earth.
Examples include, Proxima Centauri (mag. +11.1) and Barnard's star (mag. +9.5).