Temperature:

* Blue stars: Extremely hot, with surface temperatures ranging from 10,000 to 50,000 Kelvin or more.

* Red stars: Relatively cool, with surface temperatures ranging from 2,500 to 3,500 Kelvin.

Luminosity:

* Blue stars: Extremely luminous, radiating vast amounts of energy.

* Red stars: Less luminous, radiating less energy.

Size:

* Blue stars: Often massive, sometimes several times larger than our Sun.

* Red stars: Typically smaller than our Sun, sometimes only a fraction of its size.

Lifetime:

* Blue stars: Short-lived, burning through their fuel rapidly. They might only live for a few million years.

* Red stars: Long-lived, burning their fuel slowly. They can live for billions of years, sometimes much longer than the age of the universe.

Composition:

* Blue stars: Composed mainly of hydrogen and helium, but with a higher percentage of heavier elements.

* Red stars: Also composed primarily of hydrogen and helium, but with a lower percentage of heavier elements.

Spectral Class:

* Blue stars: Classified as O and B stars.

* Red stars: Classified as K and M stars.

Evolution:

* Blue stars: Eventually explode as supernovae, leaving behind neutron stars or black holes.

* Red stars: Gradually evolve into white dwarfs, then eventually cool down to become black dwarfs.

Examples:

* Blue stars: Rigel (Orion), Spica (Virgo)

* Red stars: Betelgeuse (Orion), Proxima Centauri (Centaurus)

In summary:

Blue stars are hot, massive, luminous, and short-lived. They burn through their fuel quickly and explode as supernovae. Red stars are cool, smaller, less luminous, and long-lived. They burn their fuel slowly and eventually evolve into white dwarfs. These differences arise primarily due to the differences in their mass and temperature.