What is the Wayback Machine?

“The Internet Archive is a San Francisco–based nonprofit digital library with the stated mission of “universal access to all knowledge”.[4][5] It provides free public access to collections of digitized materials, including websites, software applications/games, music, movies/videos, moving images, and nearly three million public-domain books. As of October 2016, its collection topped 15 petabytes.[6] In addition to its archiving function, the Archive is an activist organization, advocating for a free and open Internet.”