Redshift is a term commonly used in astronomy to describe the phenomenon where light from distant galaxies or celestial objects appears to be shifted towards longer wavelengths. This shift is caused by the Doppler effect, where objects moving away from the observer exhibit a redshift in their spectrum. By measuring the redshift of objects in space, researchers can determine their distance from Earth and gain insights into the expansion of the universe. Redshift is a crucial tool in studying the evolution and structure of the universe.