Question

What is cosmic background radiation?

Answer 1

Cosmic background radiation is electromagnetic radiation from the sky with no discernible source. The origin of this radiation depends on the region of the spectrum that is observed. 

Answer 2

Cosmic background radiation is the energy left over from the big bang and it's everywhere we look so if we consider ourselves the center, no matter which way we look we see this cosmic background radiation which is left over energy from the big bang.