Astronomy is an exciting field of science that has fascinated people since the beginnings of recorded history. Ancient civilizations searched the heavens in wonder, some recording on clay tablets what they observed. Many religious and philosophical beliefs were originally based on interpretations of these ancient observations. Today, we are still awed by space, but now we are fascinated with ideas of space travel, black holes, and the search for extraterrestrial life. Throughout history, people have speculated about the universe and their place in it and watched the sky and wondered. What is out there and what does it all mean? Are there other people on other planets, looking at the star in their sky that is our sun, wondering if we exist?

Until about thirty years ago progress in astronomy was limited to what could be observed and photographed. Developments in technology then began to provide the details of what is happening in the larger expanses of space away from the earth. This included new data made available from the development of infrared, radio, and X-ray telescopes and the Hubble Space Telescope. New data and the discovery of pulsars, neutron stars, and black holes began to fit together like the pieces of a puzzle. Theoretical models emerged about how stars, galaxies, and the universe have evolved. This chapter is concerned with these topics and how the stars are arranged in space. The chapter concludes with theoretical models of how the universe began and what may happen to it in the future.