Telescopes that are sensitive to electromagnetic radiation in the microwave range can detect a faint signal from all directions in outer space. This signal, called the Cosmic Microwave Background Radiation (or CMBR for short), is a faint remnant from the early history of the universe. It is significant evidence for the Big Bang.
Cosmology is a field of physics devoted to understanding questions about the large-scale structure and evolution of the universe. The generally accepted theory for the origin of the universe is the Big Bang. Three possible outcomes for the future of the universe are the Big Crunch, the Big Rip, and the Big Freeze. Cosmology also encompasses the study of dark matter and dark energy.