These facsimile images of measured drawings, photographs, and written documentation cover 35,000 significant historic sites dating from the 17th to the 20th century. The Historic American Buildings Survey (HABS) started in 1933 as a work relief program and became a permanent part of the National Park Service the following year to document "our architectural heritage of buildings," in the words of project founder Charles E. Peterson. The Historic American Engineering Record (HAER) was established in 1969 to similarly survey engineering works and industrial sites.

For each structure, the site provides from one to ten drawings, from one to 30 photographs, and from one to 50 pages of HABS text detailing the structure's history, significance, and current physical condition. The collection displays building types and engineering technologies from a farmhouse to a pickle factory, from churches to the Golden Gate Bridge.

With more than 375 documents related to United States history from the colonial period to the present, this site provides important historical documents and speeches. "Essays" contains more than 35 writings on various aspects of United States history. "Biographies" offers more than 200 biographies of historical figures related to American history, ranging from 350 words to 2,000 words in length. "Presidents" contains documents pertaining to each United States president, including inaugurations and State of the Union addresses.

Documents and essays are hyperlinked to four editions of the booklet An Outline of American History (1954, 1963, 1990, and 1994), a publication distributed abroad by the United States Information Service, along with similar volumes on American economy, government, literature, and geography. The site provides basic primary sources for American history survey courses.

This massive collection presents more than 550,000 images relevant to both U.S. and world history, from the earliest days of print culture to the present. Resources consist primarily of historical maps, posters, prints and photographs, illuminated manuscript pages, and images drawn from published books.

For browsing, the materials are divided by subject heading, library of origin, and the name of the item's creator and/or publisher. They are also sorted by collection: Arts & Literature; Cities & Building; Culture & Society; History & Geography; Industry & Technology; Nature & Science; and Printing & Graphics. Within these broad headings, images are further subdivided into more specific groupings, for example, Indonesian dance, dress and fashion, Civil War medical care, and New York City apartment buildings. All images can be downloaded and are accompanied by detailed source information, but users will have to turn elsewhere for historical context.

These audio files, abstracts, transcriptions of oral arguments, and written opinions cover more than 3,300 Supreme Court cases. Materials include 3,000 hours of audio arguments in selected cases since 1955 and all cases since 1995. Users can access cases through keyword searches or a list of thirteen broad categories, such as civil rights, due process, first amendment, judicial power, privacy, and unions.

Cases include Roe v. Wade (abortion), Gideon v. Wainwright (right to counsel), Plessy v. Ferguson (segregation), Grutter v. Bollinger (affirmative action), and Bush v. Gore (election results). Biographies are provided for all Supreme Court justices and "The Pending Docket" provides briefs and additional materials on upcoming cases. The website also includes links to written opinions since 1893 and podcasts featuring discussions of cases starting in 1793.