The U.S. Census Bureau conducts several data collection programs about the U.S. population which have their own language, geography, and data portals. This guide is based on a similar guide created by Jacquelyn Daniel at RWWL.
Data for the 2000 and 1990 Census of Population and Housing are available via an interactive online tool American FactFinder. Full text of census publications with more detailed data are also available in PDF format.