This document summarizes key facts about the 2011 Tohoku earthquake and tsunami in Japan. It was a magnitude 9.0 earthquake that caused around 20,000 deaths and over $200 billion in damage. Although preparations were in place for a magnitude 8 quake, the scale of the event overwhelmed defenses. It also triggered a nuclear disaster at the Fukushima power plant. Analysis of the seismic data provides insights into the tectonic setting and rupture process of the devastating quake.