What has a red shift and cosmic background radiation?

A redshift is observed in distant galaxies and cosmic background radiation is primarily associated with the Cosmic Microwave Background (CMB). The redshift indicates that these galaxies are moving away from us, which supports the expansion of the universe, a key aspect of the Big Bang theory. The CMB, discovered in 1965, is the afterglow radiation from the early universe, providing evidence of its hot and dense state shortly after the Big Bang. Together, they offer crucial insights into the universe's origins and its expansion over time.