The Laser Interferometer Gravitational-wave Observatory is the largest component in a worldwide effort to detect gravitational waves reaching the Earth. Potential sources of detectable gravitational waves include binary systems of neutron stars or black holes; core collapse supernovae; cosmic strings; rapidly spinning neutron stars; and a cosmic gravitational wave background. After several years of commissioning, the LIGO detectors have reached their sensitivity goals and are now collecting data. I will give an overview of the LIGO project, describe how the detectors have been engineered to detect incredibly weak signals, and highlight some recent astrophysics results and ongoing searches for gravitational waves.