The United States Holocaust Memorial Museum’s Holocaust Encyclopedia is the most visited and comprehensive Holocaust resource online today. It provides the public, educators, faculty, students, and scholars with hundreds of articles, access to digitized collections, critical thinking and discussion questions, lesson plans, oral histories, videos, and much more.
Research in Ministry® (RIM®) is a thesis and dissertation abstract database where users can search for and share the outcomes of research conducted in programs of study related to ministry, theology and religion. 
For more than 40 years, the Hartford Institute for Religion Research has a record of rigorous, applied research on religious organizations, including the study of churches, denominations, seminaries, and other religious communities. Their work is guided by a disciplined understanding of the interrelationship between the life and resources of American religious institutions and the possibilities and limits placed on those institutions by the social and cultural context in which they work.
Founded in 1985, the Gay, Lesbian, Bisexual, Transgender (GLBT) Historical Society is recognized internationally as a leader in the field of LGBTQ public history. The GLBT Historical Society collects, preserves, exhibits and makes accessible to the public materials and knowledge to support and promote understanding of LGBTQ history, culture and arts in all their diversity.
Data.census.gov is the primary platform to access data and digital content from the United States Census Bureau. 
Disciples of Christ Historical Society has preserved the many documents, books, periodicals, audio and visual materials, and precious artifacts that tell the story of the Stone-Campbell heritage. Disciples History provides a history of the Stone-Campbell Tradition, biographies of notable people, and a list of Disciples of Christ periodicals.
The purpose of the Digital Transgender Archive (DTA) is to increase the accessibility of transgender history by providing an online hub for digitized historical materials, born-digital materials, and information on archival holdings throughout the world. 
The Digital Public Library of America Primary Source Collections explore topics in history, literature, and culture developed by educators — complete with teaching guides for class use. 
The Digital Public Library of American Exhibitions showcases stories of national significance drawn from source materials in libraries, archives, and museums across the United States. 
The David Rumsey Historical Map Collection contains more than 150,000 maps dating from 1500 to the present. The collection focuses on rare 16th through 21st century maps of North and South America, as well as maps of the World, Asia, Africa, Europe, and Oceania. The David Rumsey Historical Map Collection includes atlases, wall maps, globes, school geographies, pocket maps, books of exploration, maritime charts, and a variety of cartographic materials including pocket, wall, children’s, and manuscript maps.