Why are stars different colors?

Red giants. White dwarfs. Stars come in different colors. The reason they come in different colors is because they have different surface temperatures. Stars are arranged by spectral class; from hot to cool, the classes are O, B, A, F, G, K, M, L, T, and Y. The hottest stars (O and B) with surface temperatures of more than 10,000 kelvins (K) are blue to bluish white. Class A stars, which have surface temperatures of...