The first sixteen years of the twenty-first century have seen tumultuous and life-changing events- terror, wars, natural disasters, as well as social and political events that will render the world forever changed. This text documents it all, covering events such as the 9/11 attack on the Twin Towers, the wars in Afghanistan and Iraq, natural disasters around the globe, and the election of the first African-American President. It also features important social and cultural developments, including the rise of digital and social media, as well as breakthroughs in science and medicine. In-depth, yet accessible essays provide a summary of the event and discuss the event's significance and historical impact. Entries are supplemented with sources for further reading, cross-references to other material in the series, maps, quotations from primary source documents, timelines, and hundreds of photographs and illustrations.