The Universe is like a pick n’ mix store when it comes to the variety of stars that it contains.
The colour of a star gives astronomers information about how heavy it is and the temperature of its surface. The hottest and heaviest stars are blue, while the coolest and lightest ones are red. (This is the opposite of how we use blue and red for hot and cold in everyday life, such as on water taps and weather reports.)
ESO/L. Calçada/S.E. de Mink