Check out these tips when deciding to use an online source. Always be skeptical.
Authority: Who is responsible for creating the web page? Is there a publisher or sponsor of the web page? Can you find information about the author and publisher?
Audience: Who is this web site created for? Is the content geared towards an age group or population group?
Accuracy: How does the information compare to other sources?
Content: What is the content of the web site: images, articles, a blog? The type of domain (.edu, .gov, .org) may provide some clues about the information. Can you detect a bias? Are there cited references?
Currency: How recent is the web site? Is there information on when it was last updated?
DPLA connects people to the riches held within America’s libraries, archives, museums, and other cultural heritage institutions. All of the materials found through DPLA—photographs, books, maps, news footage, oral histories, personal letters, museum objects, artwork, government documents, and so much more—are free and immediately available in digital format. The cultural institutions participating in DPLA represent the richness and diversity of America itself, from the smallest local history museum to our nation’s largest cultural institutions.
HathiTrust is a partnership of academic & research institutions, offering a collection of millions of titles digitized from libraries around the world. It is a great resource for primary source material.
Significant primary materials from all countries and cultures, available in multilingual format. Content includes books, manuscripts, maps, newspapers, journals, prints and photographs, sound recordings, and films.
WDL items can be browsed by place, time, topic, type of item, language, and contributing institution. The search feature can be used to search all of the descriptions and the full text of printed books on the site. The WDL is a project of the U.S. Library of Congress, carried out with the support of the United Nations Educational, Cultural and Scientific Organization (UNESCO), and in cooperation with libraries, archives, museums, educational institutions, and international organizations from around the world.