Internet

• 1. Introduction

  ›

  The word internetted appeared as early as 1849, meaning interconnected or interwoven, long before anyone could send a message across the planet in a heartbeat. The Internet that the word now describes is the global system of interconnected computer networks. It links private, public, academic, business, and government networks of local to global scope. No single body governs it. Each constituent network sets its own policies, yet somehow billions of devices find one another. How did a Cold War research project grow into a network with no center? Why do the words Internet and World Wide Web get confused so often? And how did a system with no owner come to carry more than 97 percent of all telecommunicated information by 2007? The answers begin with a handful of researchers who imagined that separate networks might one day speak as one.

• 2. A Network Of Networks

  ›

  In the 1960s, computer scientists began building systems for the time-sharing of computer resources, letting many users draw on one machine. J. C. R. Licklider proposed the idea of a universal network while at Bolt Beranek & Newman, then led the Information Processing Techniques Office at the Advanced Research Projects Agency. His vision needed a way to move data. Paul Baran at RAND in the early 1960s and, independently, Donald Davies at the United Kingdom's National Physical Laboratory in 1965 developed packet switching, one of the Internet's foundational technologies. After the Symposium on Operating Systems Principles in 1967, packet switching from the proposed NPL network was folded into the design of the ARPANET. On the 29th of October 1969, ARPANET began with two nodes, linking the University of California, Los Angeles and the Stanford Research Institute. The University of California, Santa Barbara came third, followed by the University of Utah. By the end of 1971-15 sites were connected, and the network spread to remote centers and military bases across the United States.

• 3. Speaking One Language

  ›

  Early international links for the ARPANET were rare. In 1973, connections reached Norway and Peter Kirstein's research group at University College London, which opened a gateway to British academic networks. The deeper problem remained: how could separate networks merge into a single network of networks? In 1974, Vint Cerf at Stanford University and Bob Kahn at DARPA published a proposal titled "A Protocol for Packet Network Intercommunication". Cerf and his graduate students used the term internet as shorthand for internetwork, a usage that the Internet Experiment Notes and later RFCs carried forward. The work of Louis Pouzin and Robert Metcalfe shaped the resulting TCP/IP design. The set of protocols grew from research commissioned in the 1970s by the Defense Advanced Research Projects Agency, working with universities and researchers across the United States, the United Kingdom, and France. In 1982, the Internet Protocol Suite was standardized, opening the way for interconnected networks to spread worldwide.

• 4. From Research To Public Use

  ›

  Access to the ARPANET widened in 1981 when the National Science Foundation funded the Computer Science Network. In 1986, the National Science Foundation Network reached supercomputer sites for researchers, first at 56 kbit/s and later at 1.5 Mbit/s and 45 Mbit/s. The NSFNet expanded into Europe, Australia, New Zealand, and Japan in 1988 to 1989, the start of the Internet as an intercontinental network. Commercial Internet service providers emerged in 1989 in the United States and Australia, and the ARPANET was decommissioned in 1990. In mid-1989, MCI Mail and Compuserve connected to the Internet, delivering email to the half million users then online. On the 1st of January 1990, PSInet launched an alternate backbone for commercial use. In March 1990, the first high-speed T1 link between the NSFNET and Europe ran between Cornell University and CERN. By 1995, the Internet was fully commercialized in the United States when the NSFNet was decommissioned, lifting the last restrictions on commercial traffic. The volume of traffic began doubling every 18 months, a pattern formalized as Edholm's law.

• 5. The Web Is Not The Internet

  ›

  Tim Berners-Lee began writing WorldWideWeb, the first web browser, in 1990, after two years of lobbying CERN management. By Christmas 1990 he had built every tool a working Web needed: HyperText Transfer Protocol 0.9, HyperText Markup Language, the first browser, the first HTTP server software later known as CERN httpd, and the first web pages, which described the project itself. People often treat the terms Internet and World Wide Web as the same thing, speaking of going on the Internet when they open a web browser. The Web is only one of many Internet services. It is the global collection of web pages, documents, and other resources linked by hyperlinks and Uniform Resource Identifiers. HTTP is its main access protocol. Browsers such as Microsoft Edge, Mozilla Firefox, Opera, Apple's Safari, and Google Chrome let users move from page to page through embedded hyperlinks. Email, file sharing, and Internet telephony each run alongside the Web, not within it.

• 6. Counting The Connected

  ›

  Between 2000 and 2009, the number of Internet users worldwide rose from 390 million to 1.9 billion. By 2010-22 percent of the world's population had access to computers, with 1 billion Google searches a day and 2 billion videos viewed daily on YouTube. In 2014, users surpassed 3 billion, or 44 percent of the world, though two-thirds came from the richest countries. By 2018, Asia alone accounted for 51 percent of all users, with 2.2 billion of the world's 4.3 billion. China's Internet users reached 802 million in 2018, followed by India with some 700 million and the United States with 275 million. In 2022, China had a 70 percent penetration rate, against India's 60 percent and the United States's 90 percent. As of 2025, the International Telecommunication Union estimated that 6 billion people, or 74 percent of the world's population, used the Internet, while 2.2 billion remained offline. After English at 27 percent, the most requested languages on the Web are Chinese at 25 percent and Spanish at 8 percent, a spread that standards like Unicode help carry.

• 7. Order Without A Ruler

  ›

  The Internet operates without a central governing body, a feature often credited for its organic growth. The non-profit Internet Engineering Task Force handles the technical underpinning and standardization of the core protocols, IPv4 and IPv6. Its standard-setting work groups are open to any individual, and their results appear as Request for Comments documents. The Internet Corporation for Assigned Names and Numbers administers the principal name spaces, coordinating domain names, IP addresses, and port numbers. The National Telecommunications and Information Administration, an agency of the United States Department of Commerce, held final approval over changes to the DNS root zone until the IANA stewardship transition on the 1st of October 2016. Five Regional Internet registries assign address blocks, among them AfriNIC for Africa and RIPE NCC for Europe, the Middle East, and Central Asia. The Internet Society, founded in 1992, gives an administrative home to several of these groups. In 2016, the Oxford English Dictionary found that across roughly 2.5 billion sources, "Internet" was capitalized in 54 percent of cases.

• 8. Addresses And Their Limits

  ›

  Internet Protocol version 4 defines an IP address as a 32-bit number. Designed in 1981, IPv4 was built to address up to roughly 4.3 billion hosts, a ceiling the network eventually hit. IPv4 address exhaustion entered its final stage in 2011, when the global allocation pool ran out. A successor was already in motion: IPv6, developed in the mid-1990s, uses 128 bits and was standardized in 1998. By design, IPv6 is not directly interoperable with IPv4, so it runs as a parallel version of the Internet, with translation facilities bridging the two. Beneath the addressing sits the protocol suite, ordered into four layers, from the application layer where a web browser exchanges HTTP and HTML, down to the link layer that carries technologies such as Wi-Fi, Ethernet, and DSL. That layered design is fragile in the physical world. In 2011, a woman digging for scrap metal severed most connectivity for the nation of Armenia, a reminder that a network of billions can still ride on a single buried cable.