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The document discusses the history and development of the internet over the past 50 years, from its origins as a US military program called ARPANET to expand researchers' access to computers, to its commercialization and widespread adoption in the 1990s as the World Wide Web popularized access through graphical web browsers. It enabled new forms of communication and sharing through email and bulletin boards that helped build online communities, and its non-proprietary protocols allowed it to scale globally in a decentralized way.