#4: Archive.org – Documents the Structural History of the World Wide Web
Brewster Kahle founded the Internet Archive in 1996 to build a digital library for internet sites and cultural artifacts. The famous Wayback Machine feature lets you type in any web address to see exactly how that page looked 20 or 30 years ago. The system has preserved over 800 billion captures of digital history. Journalists, historians, and nostalgic users use it to retrieve lost information, view dead pages, and track the evolution of modern corporations.
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