* Sun: Our Sun is a yellow dwarf star, a fairly average star in terms of brightness.

* Blue supergiant: These stars are incredibly hot and massive, making them extremely luminous.

* White dwarf: White dwarfs are the remnants of stars like our Sun after they've exhausted their fuel. They are incredibly dense but small, and emit very little light.

* Red giant: Red giants are much larger than our Sun, but cooler. While they are brighter than our Sun, they are not as bright as blue supergiants.

In summary: White dwarfs are the least bright of the stars listed.