The home of the U.S. Government’s open data. Find data, tools, and resources to conduct research, develop web and mobile applications, design data visualizations, and more.
This is the primary access point for Official U.S. Census Bureau data covering state, county, or city levels.
Note: Data.Census.gov replaced American FactFinder as the primary access point for Census data in July 2019. Although the old site still works--and provides some functionality not found yet in Data.Census.gov--no NEW data is being added to American FactFinder.
This collection focuses on rare 18th and 19th century North and South America maps, but there are also maps of the World, Europe, Asia, and Africa. Includes atlases, globes, school geographies, books, maritime charts, and a variety of separate maps.
DOI stands for "Digital Object Identifier." They provide a stable "address" that links to online items and are often included when making a reference citation. This is the "official" source for information about DOIs, including: an Introductory Overview, a long list of Frequently Asked Questions, and the complete DOI Handbook (note: this link uses a DOI).
DPLA provides free, online access to digitized material from America’s libraries, archives, and museums. It covers a wide range of topics, including the written word, works of art and culture, America’s heritage, and science.
DOAJ provides free, full-text access to thousands of "Open Access Journals." These scientific and scholarly journals cover many subjects (and languages).
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