SCExAO, or Subaru Coronagraphic Extreme Adaptive Optics, is a high-contrast imaging instrument mounted on the Subaru Telescope in Hawaii. It is designed to directly image exoplanets and disks around nearby stars by suppressing the light from the central star to reveal fainter companions. SCExAO uses a combination of adaptive optics, coronagraphy, and wavefront control techniques to achieve high contrast imaging and is used to study the formation and evolution of planetary systems. The instrument is also used to study the structure and dynamics of protoplanetary disks, the atmospheres of giant planets, and the properties of brown dwarfs.