This chapter contains sections titled: The Big Picture What Is Photovoltaics? Six Myths of Photovoltaics History of Photovoltaics PV Costs, Markets and Forecasts What Are the Goals of Today's PV Research and Manufacturing? Global Trends in Performance and Applications Crystalline Silicon Progress and Challenges Thin Film Progress and Challenges Concentration PV Systems Balance of Systems Future of Emerging PV Technologies Conclusions References