Virtual archives (digital materials only)

Led by the Internet Archive, a substantial number of the world's historical repositories are digital-only, and are accessed solely through the internet. Some, like Common Crawl Foundation, constrain their content to internet documents and artifacts, others have both natively-digital items, and digitized versions of physical things in their collections. The volume of digital materials available in today's virtual archive is vast. As of this writing, the Internet Archive has officially captured 1 trillion web pages.