"The materials on this Web site include a U.S. history textbook; over 400 annotated documents from the Gilder Lehrman Collection on deposit at the Pierpont Morgan Library, supplemented by primary sources on slavery, Mexican American and Native American history, and U.S. political, social, and legal history; succinct essays on the history of film, ethnicity, private life, and technology; multimedia exhibitions; and reference resources that include a searchable database of 1,500 annotated links, classroom handouts, chronologies, glossaries, an audio archive including speeches and book talks by historians, and a visual archive with hundreds of historical maps and images. The site's Ask the HyperHistorian feature allows users to pose questions to professional historians."