What is Cosmic Microwave Background Radiation

Cosmic microwave background radiation is like the leftover heat and light from the Big Bang. This leftover heat and light is everywhere in the universe. What’s really cool is that we can see a bit of it on an old TV set. When a TV isn’t showing any channel, you see black and white fuzz and hear a hissing sound. About 1% of this fuzz and hissing is actually cosmic microwave background radiation - it’s like a faint echo from when the universe began.