Provides links to more than 165,000 full-text digital books from more than 1800 commercial and non-commercial publishers, universities, and various private sites. More than 140,000 of these books, texts, and documents are available free.

DPLA is an all-digital library that aggregates metadata from libraries, museums and institutions around the country. It provides an easy to use search interface. Individuals can create search guides or "Primary Source Collections" which are useful for researching topics.

A digital library of ten thematic collections of primary sources for the study of southern history, literature, and culture.

Search across many disciplines and sources including open access journals and institutional repositories.

A non-profit library of millions of free books, movies, software, music, websites, and more.

The Library of Congress is the nation's oldest federal cultural institution and serves as the research arm of Congress. It is also the largest library in the world, with millions of books, recordings, photographs, maps and manuscripts in its collections.

A digital library of primary sources in 19th century social history. Includes approximately 10,000 books and 50,000 journal articles.

A library of close to 50,000 free eBooks, with a selection of classic political and philosophical texts.

Supported by the Open Education Network, the Open Textbook Library offers over 800 eTextbooks that are licensed by authors and publishers to be freely used and adapted. Download, edit and distribute them at no cost.

Public domain materials held by the Smithsonian Libraries.