Astronomers have long looked in vain for evidence of worlds orbiting other stars, but technological advances have made such discoveries far more regular. Several teams continuously work on the planet search using a variety of techniques and equipment; as a result, we know of 161 planetary candidates in 135 star systems, from 8.25 to 9,000 light-years from Earth. This work summarizes information on all the extrasolar planets discovered. Each planet is described in as much detail as is available with graphs indicating how the planet orbits its primary. Details on the primary are given. Additionally, the boundaries of the habitability zone around each star are plotted, and information about the likelihood of terrestrial planets existing in each system is provided. Five appendices are included on such topics as withdrawn and tentative discoveries, the constellations, and masses and orbital characteristics of extrasolar planets.