Finding and Characterizing Extrasolar Planets with \emph{Kepler}

NASA's \emph{Kepler} spacecraft launched successfully on 2009 March 6. Its mission is to find the first rocky Earth-like planets orbiting stars other than the Sun. In particular, \emph{Kepler} will measure the frequency of rocky planets in the galaxy, determining whether our solar system is rare, typical, or something in between. I will discuss the current state of scientific knowledge about extrasolar planets, how \emph{Kepler} will contribute, and what we might learn about those planets that we find in the coming years.