The goal of onion routing was to have a way to use the internet with as much privacy as possible, and the idea was to route traffic through multiple servers and encrypt it each step of the way. This is still a simple explanation for how Tor works today.
https://support.torproject.org
https://www.theguardian.com/us-news/the-nsa-files
https://soundcloud.com/bitcoinprimitives
https://www.torproject.org/about/history/
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