The internet increasingly pervades our lives, delivering information to us no matter where we are. It takes a complex system of cables, servers, towers, and other infrastructure, developed over decades, to allow us to stay in touch with our friends and family so effortlessly. Here are 40 maps that will help you better understand the internet — where it came from, how it works, and how it's used by people around the world.
ARPANET, the precursor to the modern internet, was an academic research project funded by the Advanced Research Projects Agency, a branch of the military known for funding ambitious research projects without immediate commercial or military applications. Initially, the network only connected the University of Utah with three research centers in California. ARPANET was a test of a then-novel technology called packet-switching, which breaks data into small "packets" so they can be transmitted efficiently across the network. It also had a more practical goal: allowing more efficient use of expensive computing resources. Computer scientists sometimes used ARPA money to buy computers, and the agency hoped that ARPANET would allow universities to share these expensive resources more efficiently. One of the first ARPANET applications was Telnet, which allowed a researcher at one ARPANET site to log into a computer at another site.
By the end of 1970, ARPANET had grown to 13 nodes, including East Coast schools like Harvard and MIT. Among the early nodes was Bolt, Beranek, and Newman (BBN), an engineering consulting company that did the engineering work required to build ARPANET. Each ARPANET site had a router known as an Interface Message Processor. These cost $82,200, or half a million dollars in today's money.
In 1973, the ARPANET became international, with a satellite link connecting Norway and London to the other nodes in the United States. Hawaii also joined the network by satellite. At this point, the network had around 40 nodes. New ARPANET applications had begun to emerge. Email was invented in 1971 by a BBN engineer named Ray Tomlinson, who also invented the use of the "@" symbol in email addresses. The File Transfer Protocol, which is still used today, allowed ARPANET users to send files to each other.
As the ARPANET entered its second decade, it was still largely confined to the United States. Academic institutions depended on federal funding to join the network, so the number of nodes expanded slowly. By 1982, the network only had about 100 nodes. But that was enough to support a vibrant online community. Long before Facebook and Twitter, ARPANET allowed computer scientists who had access to the network to stay in touch. A new bulletin board system called Usenet was invented in 1980 and caught on quickly. Usenet was organized by topic, allowing users to swap programming tips, recipes, jokes, opinions about science fiction, and much more.
Originally, the entire ARPANET was managed by the military. But network operators realized that a centralized network would eventually become unmanageable if it continued to grow. They decided that the network should be reorganized as a decentralized "network of networks." Under this scheme, different networks would be controlled by different organizations, but all the networks able to communicate using shared standards, forming a shared "internet." The military asked the computer scientists Robert Kahn and Vint Cerf to develop new networking standards to make this possible. The result was a set of standards known as TCP/IP. These standards specified the basic format of data packets transmitted across the internet. On January 1, 1983, the ARPANET switched to using TCP/IP, marking the birth of the modern internet. The switch to TCP/IP didn't make much difference from a user perspective — applications like email and Telnet worked about the same as they had before. But the new standard paved the way for much faster network growth by lowering the barrier to entry for new networks. One of the first new networks to connect to the new internet was CSNET, which was funded by the National Science Foundation to link computer science departments across the country. This map shows the location of ARPANET and CSNET nodes (labeled "Phonenet"), which after 1983 communicated with each other using TCP/IP. By the time the ARPANET was decommissioned in 1990, it was just one of many networks that comprised the internet. Today, the internet is made up of more than 40,000 different networks. These networks still communicate with each other using the TCP/IP standards Cerf and Kahn developed in the 1970s.
During the 1980s, the National Science Network funded several supercomputing centers around the United States. And in 1986 the agency created a TCP/IP-based network called NSFNET to link those supercomputing centers together and allow researchers across the country to use them. The primary goal was to allow computer science researchers to log into the supercomputers and perform academic research. But NSF decided not to limit NSFNET to that purpose, allowing the network to be used for a wide variety of academic purposes. As a result, the NSFNET became the internet's "backbone," the high-speed, long-distance network that allowed different parts of the internet to communicate. Schools that didn't have a direct connection to the NSFNET worked together to build regional networks that linked them to each other and to the nearest NSF node. This shows the NSFNET as it existed in 1992. By this time, there were 6,000 networks connected to NSFNET, with a third of them located overseas. That meant that students and faculty at a growing number of universities had access to email, Usenet, and even a recently-invented application called the World Wide Web. And although the NSFNET was officially restricted to non-commercial use, for-profit companies were increasingly connecting to the network as well, setting the stage for the commercialization of the internet that followed.
In 1993, the internet was still dominated by the United States but it was becoming a truly global network. This is a map of information flow on Usenet, an bulletin board application that allowed users to swap recipes, jokes, programming tips, and more.
In 1994, the Clinton Administration privatized the internet backbone. Commercial firms took over the job of carrying long-distance internet traffic, allowing the government-funded NSFNET to be decommissioned. Officials were careful to ensure that no single company controlled too much of the backbone, helping to create a competitive market for internet connectivity that still exists today. These four maps illustrate how the market had evolved by the turn of the century. Four of the largest private long-distance network providers were UUNet, AT&T, Sprint, and Level 3. Each had its own nationwide (and global) network, and they competed with each other to provide long-distance connectivity to smaller networks. UUNet became part of WorldCom in 1996, and became part of Verizon in 2006. Today, Verizon operates one of the world's largest internet backbones, in competition with AT&T, Sprint, Level 3 and many other companies.
By 2000, almost half of Americans were on the internet, but ordinary people in most other countries had not yet joined the network. There were fewer than 400 million internet users worldwide. Since then, the internet has gone from an American network to a truly global one. This map illustrates how the internet came first to wealthy countries, then to middle-income countries, and finally to poor countries. Today, there are more than 2.5 billion internet users, and hundreds of millions of new users are joining each year.
There are two basic ways people can log onto the internet: through a fixed broadband connection at home or in an office and via a wireless connection on a cell phone or tablet. This data from the International Telecommunications Union shows how popular fixed internet access is around the world. It shows internet access is widespread in most parts of the world, but is still fairly scarce in much of sub-Saharan Africa and the Middle East. Fixed internet access allows multiple devices in a customer's home to access the internet. Fixed connections are also ideal for streaming-video services such as Netflix because they tend to have greater capacity than wireless networks.
This map shows the percentage of consumers around the world who have mobile internet access (note that the colors on this map are not directly comparable to the previous map). In the developed world, people usually got fixed internet access first and obtained mobile internet devices later. But some developing countries are skipping the construction of fixed broadband networks altogether. This is cost-effective because a single cell phone tower can provide service to hundreds of customers. For examle, 2.7 percent of Egyptians have fixed broadband service at home, but 10 times as many Egyptians have internet access using a cell phone. The story is similar in Ghana, Uzbekistan, Indonesia, South Africa, and Nigeria. Mobile internet access can have profound implications for people in isolated areas. Farmers can use mobile phones to learn about recent market developments, increasing the amount they can get for their crops. Some mobile phone operators also offer sophisticated payment capabilities, allowing people who don't have access to the conventional banking system to make electronic payments. A few wealthy countries, including Japan, South Korea, and Sweden, that have more mobile internet subscriptions than people. Some customers have two more or smartphones, tablets, or other connected mobile devices.
Internet access is a lot faster in some places than others. According to Speedtest.net, a website that lets users test their own internet connections, the fastest internet in the world is in Hong Kong, with an average of almost 80 million bits per second (Mbps). Other high-speed countries include Japan, South Korea, Sweden, Romania, the Netherlands, and Switzerland. The United States clocks in at number 30, with average speeds of 24 Mbps. These figures are worth taking with a grain of salt because they're based on a self-selected sample. Users must visit the speedtest.net website to test their own broadband speeds, and it stands to reason that users with fast connections would be most likely to try it. Still, the data permits interesting cross-country comparisons.
For the internet to work, everyone needs a unique Internet Protocol (IP) address. To coordinate the distribution of these addresses, the internet is broken up into five zones. Each zone has been assigned hundreds of millions of IP addresses to manage. Unfortunately, the original internet architecture, called IPv4, only allows for about 4 billion addresses, and the network has nearly exhausted the supply. The problem is particularly growing in fast-growing regions like Asia. Engineers have developed a long-run solution to this problem: switching to a new internet standard called IPv6. IPv6 offers such a large number of potential addresses that the world will never run out. But adoption of IPv6 has been slow. Today, the overwhelming majority of internet traffic uses the old standard. But with few IPv4 addresses left, people joining the internet in the future will have little choice but to use IPv6.
IP addresses have a numeric format like this: 126.96.36.199. But it's easier for people to remember domain names such as vox.com. The domain name system (DNS) acts like a directory system, telling computers wanting to view a website like www.vox.com what IP address to access. The system is hierarchical: the .com domain is managed by a company caled Verisign, which has delegated to Vox the management of the vox.com domain. Domains like .com, .org, and .edu are called generic top-level domains, and they are especially popular in the United States. But other countries are more likely to use what's known as country-code top level domains (ccTLD). Every country in the world has a ccTLD. This map shows the ccTLDs in Europe. For example, the United Kingdom's ccTLD is .uk, so the British Broadcasting Service's website can be found at www.bbc.co.uk.
Even very small countries get ccTLDs. Here's a close-up of the area around Australia and the many small island nations that have their own domain names. Some of these countries realized that they could make a lot of money if they opened their domains to foreigners. The result: popular websites like last.fm (.fm is the domain of the Federated States of Micronesia) and twitch.tv (.tv is the domain for the island nation of Tuvalu). The .io domain, assigned to the British Indian Ocean Territory, has become popular among programmers. They associate the domain with the technical term input/output and use it to create "artisinal websites." Click to see a full world map.
Today the fastest way to transmit information over long distances is with fiber optics — long, thin strands of glass that carry information as pulses of light. Because a single fiber can transmit as much as 100 billion bits per second (100 Gbps, about ten thousand times faster than a typical home broadband connection) and a cable can contain hundreds of fibers, a single cable can have enough capacity for the communications of millions of users. All that data has proven irresistible to the National Security Agency, which has developed a variety of techniques to scoop up data as it flows through fiber optic cables.
Fiber optic cables are relatively fragile. In 2008, two fiber optic cables that connect Middle Eastern countries to India were cut, leading to disruptions for many internet users in Egypt and India. Some press reports suggested that the damage was caused by a ship's anchor being dragged along the bottom of the Mediterranean, but the Egyptian authorities have said no ships were in the area at the time the cables were damaged. The exact cause of the outage remains a mystery.
Sometimes internet access is disrupted due to accidents. In other cases, it's deliberate government policy. For example, during the 2011 Tahrir Square protests, the Egyptian government cut off Egypt's connections to the rest of the internet. This was possible because Egypt's links to the outside world were controlled by a handful of large companies. This map shows which countries have few enough links to the outside world to be at risk of this kind of censorship. Some countries, such as the United States, have dozens of links to the outside world, making a coordinated shutdown of the US internet almost impossible. Others have many fewer links and are correspondingly more vulnerable to censorship.
In April 2013, Syria's largest city, Aleppo, disappeared from the internet for several hours, one of several outages that have occurred during the civil war there. The southern parts of Syria receive internet access from undersea fiber optic cables, but Aleppo accesses the internet via a land connection to Turkey. It's not clear if the outage was due to accidental damage from fighting in the area, or whether the regime of Bashar al-Assad had deliberately disrupted rebel-held Aleppo's internet access. As the Washington Post's Andrea Peterson puts it, "Internet outages in Syria have a curious history of happening at times convenient for the Assad regime."
When Superstorm Sandy hit New Jersey in October 2012, it knocked a number of computers off the internet. A team of computer scientists at the University of Michigan had recently built ZMap, a tool that allowed them to scan every computer on the internet in less than an hour. That allowed them to make this map, which shows locations where the number of web servers running the SSL encryption software declined by 30 percent or more, which turns out to be a good proxy for heavy storm damage.
In most Western countries, the internet is a free-speech zone where ordinary people can express themselves without fear of censorship. But that's not true everywhere. This map from Freedom House details which countries respect freedom of speech and which countries flout it. Cuba and several countries in Southeast Asia and the Middle East engage in pervasive censorship and are marked in purple. China, for example, has a "great firewall" that makes it difficult for its citizens to read about sensitive topics such as the Falun Gong or the 1989 Tiananmen Square massacre. Other countries have a partially free internet. In Russia, for example, the government has engaged in more aggressive internet censorship since Vladimir Putin returned to power in 2012.
The social media sites Facebook, YouTube, and Twitter are frequent targets for censorious governments. This map from Mother Jones shows which countries restrict their users from accessing these sites. China doesn't just block access to Western social media sites, it has also cultivated home-grown alternatives that are under the thumb of the Chinese authorities. These social media sites enable users to engage in relatively unfettered discusion, but the providers are required to participate in an elaborate monitoring and censorship regime to ensure that sensitive topics do not receive widespread discussion.
The privatization of the internet transformed what had been an obscure academic network into a hotbed of commercial innovation. In the late 1990s, hundreds of new companies sprouted up to take advantage of these opportunities. And many of them were clustered in Silicon Valley, a strip of land on the peninsula south of San Francisco. In the mid-1990s, Silicon Valley was already home to established technology companies like Intel, Apple, Adobe, and Cisco. The dot-com boom brought a new crop of companies, including Yahoo, eBay, and Google. Since the turn of the century, newer companies such as Facebook and Nest have been founded in Silicon Valley too. Mozilla, the non-profit organizaiton behind the popular Firefox browser, is based in Mountain View, not far from Google.
We use "Silicon Valley" as a shorthand for the technology companies in the San Francisco Bay Area, but the moniker is becoming increasingly out of date. Since 2000, a growing share of internet startups are being formed not in suburbs like Mountain View or Palo Alto but in the heart of San Francisco. Twitter, Dropbox, Yelp, and Airbnb are all successful technology companies that have been founded in the last decade. And they're all located within a couple of miles of one another in a San Francisco neighborhood called Soma (for South of Market). The non-profit Wikimedia Foundation, founded in 2003 to manage Wikipedia, is also located here. One big reason this neighborhood has emerged as San Francisco's innovatin center is its proximity to the Caltrain station at 4th and King Streets. The station provides easy access to the venture capitalists and established companies at the other end of the Caltrain line in Silicon Valley.
For the first decade of the 21st century, the internet was dominated by Microsoft Internet Explorer. In 2009, the software was the most popular way to browse the web in most countries, with Firefox popular in some parts of Eastern Europe and Asia. Since then Google's Chrome browser, which first released in 2008, has exploded in popularity. It is now the most popular browser in almost every developed country. On the other hand, in much of sub-Saharan Africa, the most popular browser is Opera. This is probably because many people in these countries access the internet using their cell phones, and Opera offers a mobile browser that works well on low-end smartphones.
Right now, three companies dominate the global market for mobile phones, and they've largely divided the market by income. In wealthy countries, Apple's iPhone is popular. In middle-income countries, especially in Latin America, Eastern Europe, and the Middle East, Samsung devices have the lead. In poor countries, especially in sub-Saharan Africa, Nokia often dominates. These data are based on web browsing patterns, so it may not be a perfect reflection of the number of units sold by these companies.
In 2009, Facebook was already one of the most popular social networks in the world, but over the last five years it has become totally dominant. For example, in 2009 Brazil was dominated by Orkut, a social network created by Google in 2004. But Facebook surpassed Orkut in Brazil in 2011. One factor in Facebook's growing global popularlity is Facebook Zero. Under this program, Facebook pays the data charges for users who log into a stripped down version of Facebook from their mobile phones. The program has made Facebook accessible to millions of users who wouldn't otherwise be able to afford it.
If you've entrusted your data to Google, Facebook, Yahoo, or Microsoft, there's a good chance it's stored at a location marked by one of these pins. Smaller web companies store their servers in data centers managed by third parties, but the internet's largest companies have their own dedicated data centers with hundreds of thousands of servers in them. These data centers are located around the world. That has two advantages. First, locating data centers close to users allows data to be delivered more quickly. Second, it helps provide redundancy: if user data is kept in multiple locaitons, it will be safe even in the event of a catastrophic failure at one data center. On this map, Google data centers are red, Microsoft data centers are yellow, Yahoo data centers are purple, and Facebook data centers are blue. This is not an exhaustive list of these companies' facilities. All of these companies are secretive about their operational details, and so some of the companies' data center locations haven't been publicly disclosed.
The biggest internet companies have data centers around the world, but a disproportionate share of their data centers are located in the United States. And American data centers are clustered in a few states, notably Oregon, Iowa, and the Carolinas. These states have several important advantages. One is cheap power. For example, Oregon has cheap hydroelectric power that has attracted several companies to Oregon. Iowa and North Carolina also offer affordable electricity. Tax breaks play a role as well; Iowa recently lured a billion-dollar Microsoft data center by offering $20 million in tax incentives.
This map shows what percentage of American homes had broadband internet access in 2011. Broadband penetration in the US is heavily linked to geography. The West, Northeast, and upper midwest have the highest broadband adoption, while high-speed internet access is less common in the south.
One reason for the low levels of broadband subscription in some parts of the United States is availability. At the end of 2011, there were still significant parts of the country where fixed broadband service wasn't offered. Satellite internet service is available almost everyone in the United States, but it tends to be a lot more expensive than fixed broadband connections. And the long delays in satellite communications make it unsuitable for interactive applications such as video games and voice calls. Note that the data on this map should be taken with a grain of salt. It's the best data we have available, but it's based on self-reported data from ISPs that isn't always accurate.
Internet access in the United States is dominated by two big telephone companies — AT&T and Verizon — and two big cable companies — Comcast and Time Warner Cable. Together, those four companies account for more than two thirds of all residential internet subscriptions in the United States. Cable companies account for almost 60 percent of subscriptions, with telephone companies accounting for most of the remainder. These statistics actually overstate the amount of broadband competition in the United States, because although there are about a dozen ISPs with at least a million subscribers, most households don't have more than two options for high-speed residential internet access: a local cable monopoly and a local phone monopoly. Cable companies generally don't try to enter areas already served by other cable companies, nor do telephone companies try to poach customers from other telephone providers.
For the most part, the broadband market is dominated by the same phone and cable companies that have dominated telecommunications for decades. But one big addition to the broadband market is Google, which launched a fiber optic network in Kansas City in 2012. Since then, the search giant has added networks in Austin, TX, and Provo, UT. And Google is considering expanding into about 10 other metro areas in the American south and west.
Frustrated with poor service offered by incumbent broadband providers, about 400 municipalities across the country have built their own government-owned broadband networks. While 400 might seem like a big number, most of these towns are quite small. The largest, Chattanooga, TN, only has about 170,000 residents, and some have as few as 200. So those 400 towns account for a tiny fraction of the US population. Some of these networks are extremely fast. For example, residents of Chattanooga can get a 1000 Mbps connection — about 50 times faster than a typical connection elsewhere in the country — for $70 per month. Click for an interactive version of the map.
Incumbent broadband providers have reacted to the municipal broadband trend by arguing that it's not fair for governments to compete with the private sector. In 19 states, state legislatures have responded with legislation restricting municipalities from building their own broadband networks. That has taken some of the wind out of the sails of the municipal broadband movement, but new municipal networks keep popping up in states where the law allows them.
Social media sites like Twitter enable a lot of public discussion of the important issues of the day. But they also enable an even larger quantity of frivolous conversation. Last September was a good example. The nation was discussing two big topics: possible US involvement in a the war in Syria and Miley Cyrus's scandalous dance moves. In Washington DC, Syria conversations on Twitter were way more common than twerking conversations. But twerking was a more popular subject in most other states.
One of the amazing things about the internet is the way it permits the collection and aggregation of large-scale data about human behavior. For example, this map shows where people are tweeting about sunrises over the course of a 24-hour period. There's a yellow flash of sunrise tweets whenever the sun rises above the horizon in a part of the world. You can see an interactive version of this map here.
Viewing pornography is one of the most popular uses of the internet. This map shows data from the popular porn site Pornhub. The data suggest that liberal states such as Illinois and Massachusetts are the heaviest pornography consumers, while conservative states such as Idaho and South Dakota consume the least pornography. The average Massachusetts resident is responsible for almost twice as many pageviews per capita as the average Idaho resident. (I've omitted Kansas due to a methodological problem with Pornhub's data.)
Wikipedia is a global online encyclopedia that anyone can edit, and it has editions in more than 280 languages. Many articles are "geotagged" with a physical location. Researchers at the Oxford Internet Institute plotted these points on a map, providing a beautiful map of the locations that are subjects of Wikipedia articles. Unsurprisingly, Wikipedia contributors writing in different languages focus on different parts of the world. Most of the yellow dots from the Persian edition of Wikipedia are in or near Iran. French Wikipedia has more information about continental Europe while English Wikipedia dominates English-speaking countries. The density of information reflected by this map is amazing. Wikipedia has articles about almost every part of the Earth that's inhabited by human beings, and this map would likely be even denser if it included other major languages such as Spanish, Russian, and Chinese.
Here's another map showing which languages people around the world use online. Each dot on the map represents a cluster of tweets, and the color represents the language spoken in those tweets. English is ubiquitous online, so Fischer chose a neutral grey color for it so it wouldn't overpower the other colors. Fischer didn't explicitly label the countries on the map, but it's still easy to see national borders. You can also seem significant linguistic minorities. For example, if you click the link for the full map, you can see where people speak French in Canada.