Here's why:

* Temperature and Color: The color of a star is directly related to its surface temperature. Hotter stars emit more blue and white light, while cooler stars emit more red and orange light.

* Blackbody Radiation: Stars behave like blackbodies, meaning they emit a range of light wavelengths depending on their temperature. Cooler stars emit more energy in the longer wavelengths, which our eyes perceive as red.

Examples:

* Red Dwarf Stars: These are the most common type of star in the Milky Way and are much cooler than our Sun. They appear reddish-orange.

* Betelgeuse (Red Supergiant): This star is a cool giant, much larger than our Sun. It appears red due to its low temperature.

Important Note: The exact color of a star can be influenced by factors like its chemical composition and dust in the interstellar medium, but temperature is the primary factor.