The twentieth century witnessed some remarkable discoveries: the 1917 publication of Einstein's general theory of relativity, Carnegie astronomer Edwin Hubble's 1929 discovery of the expansion of the universe, evidence for the existence of dark matter, and the discovery of a mysterious dark energy, which is causing the universe to speed up its expansion. This comprehensive volume reviews the theory and measurement of various parameters related to the evolution of the universe. Topics include inflation, string theory, the history of cosmology in the context of measurements being made of the Hubble constant, the matter density, and dark energy, including observational results from the Sloan, Digital Sky Survey, Keck, Magellan, cosmic microwave background experiments, Hubble space telescope and Chandra. With chapters by leading authorities in the field, this book is a valuable resource for graduate students and professional research astronomers.