What does redshift do?

Redshift refers to the phenomenon where light from distant objects, such as galaxies, shifts toward longer wavelengths (the red end of the spectrum) as they move away from us. This effect is primarily due to the expansion of the universe, indicating that the farther an object is, the faster it appears to be receding. Redshift is a crucial tool in astronomy for measuring the distance and velocity of celestial objects, helping to support the Big Bang theory and our understanding of cosmic expansion. It can also occur due to gravitational effects, known as gravitational redshift.