It was born 40 years ago, in a lab at the University of California, Los Angeles. Today it wraps the entire planet and features in the daily routine of more than 1.5 billion people. Of course, it's easy to take the internet for granted and forget that it's very much a work in progress. So what forces are shaping it, how big has it grown, and will it ever evolve a mind of its own? To find out, New Scientist posed eight simple questions.
Unknown internet 1: Who controls the internet?
The official answer is no one, but it is a half-truth that few swallow. If all nations are equal online, the US is more equal than others.
Not that it is an easy issue to define. The internet is, essentially, a group of protocols by which computers communicate, and innumerable servers and cables, most of which are in private hands. However, in terms of influence, the overwhelming balance of power lies with the Internet Corporation for Assigned Names and Numbers, based in Marina Del Rey, California.
ICANN is a not-for-profit organisation that regulates online addresses, known as domain names, and their suffixes, such as ".com" and ".org". Since ICANN reports to the US government's Department of Commerce, the domain name process is effectively overseen by the US government. China, Russia and Europe have all expressed concern at this situation because it means the US has leverage over the global coordination of the internet. "It has a role that is different from the role of all other governments," says Massimiliano Minisci, a regional manager at ICANN. "That's a concern around the world."
It is not hard to see why. Take, for instance, a scenario in which a country wants to change certain aspects of its domain names. Any changes carried out at the "top" level - adding new country-level suffixes, for example - have to be checked by the US Department of Commerce, which verifies that proper procedure has been followed. Once that check has been done, the actual implementation of the change is carried out by Verisign, a US-based private company that manages the root name database, which contains the full official list of recognised suffixes. "The US government could block a modification to this database," Minisci says. "So the US can, theoretically, decide who is on the internet and who isn't."
This unsatisfactory situation will be up for discussion by the parties involved in September 2009. So what can be done?
One drastic option would be to break the internet into chunks. A more realistic idea is for more governments to get involved with ICANN, while the most straightforward option would be for the US government to release its grip on ICANN. Milton Mueller, an internet governance expert at Syracuse University in New York, considers this outcome unlikely. "No one wants to let go. The thinking is that, at the crudest level, it's something under our control, so why mess with it?"
Unknown internet 2: Could the net become self-aware?
Yes, if we play our cards right - or wrong, depending on your perspective.
In engineering terms, it is easy to see qualitative similarities between the human brain and the internet's complex network of nodes, as they both hold, process, recall and transmit information. "The internet behaves a fair bit like a mind," says Ben Goertzel, chair of the Artificial General Intelligence Research Institute, an organisation inevitably based in cyberspace. "It might already have a degree of consciousness".
Not that it will necessarily have the same kind of consciousness as humans: it is unlikely to be wondering who it is, for instance. To Francis Heylighen, who studies consciousness and artificial intelligence at the Free University of Brussels (VUB) in Belgium, consciousness is merely a system of mechanisms for making information processing more efficient by adding a level of control over which of the brain's processes get the most resources. "Adding consciousness is more a matter of fine-tuning and increasing control... than a jump to a wholly different level," Heylighen says.
How might this manifest itself? Heylighen speculates that it might turn the internet into a self-aware network that constantly strives to become better at what it does, reorganising itself and filling gaps in its own knowledge and abilities.
If it is not already semiconscious, we could do various things to help wake it up, such as requiring the net to monitor its own knowledge gaps and do something about them. It shouldn't be something to fear, says Goertzel: "The outlook for humanity is probably better in the case that an emergent, coherent and purposeful internet mind develops."
Heylighen agrees, but warns that we might find it a little disappointing. "We probably would not notice a whole lot of a difference, initially," he says.
And when might this begin? According to Heylighen, it all depends on internet fashion trends. If the effort that has gone into developing social networking sites goes into developing internet consciousness, it could happen within a decade, he says.
Unknown internet 3: How big is the net?
"The mind seemed to grow giddy by looking so far into the abyss of time," said the 18th-century scientist John Playfair, recalling the moment he learned of the Earth's long history. If Playfair could peer into the depths of the internet he might get that giddy feeling again. In 2005, Google estimated the internet contained some 5 million terabytes of data - that's more than 1 gigabyte for each of Earth's 4.5 billion trips around the sun.
There are simpler ways to appreciate the internet's sheer scale. Recent estimates suggest that well over 1 billion people rely on computers to access the internet (see graphics of internet traffic in 2002, 2004, 2006 and 2008). Yet there are also a billion or so other people who use cellphones to visit cyberspace, making them as much a part of the online community as someone surfing from a PC.
That the internet is vast is undoubted. In July 2008, web surfers were introduced to Cuil.com, billed by its designers as "the world's biggest search engine". It indexed an impressive 120 billion pages, but shortly before its launch Google announced that its systems had registered a trillion unique pages (see Internet census 2007 and 2008).
Even this might represent a fraction of what is out there. Some estimates suggest that there could be hundreds of times more information stored on the internet than Google or Cuil have so far indexed.
One thing's for sure: the internet and its contents will continue to grow rapidly. According to Google, several billion web pages are added each day. And in the minute it has taken you to read this, the total has leapt by about 700,000. Index that!
Unknown internet 4: Did the credit crunch hit the web?
Real-estate prices crashing, a big drop in growth, the threat of infrastructure collapse, and authorities printing more money to stave off disaster. No, we are not talking about the bricks-and-mortar homes and stores - things have been hitting the rocks in virtual worlds too.
The first signs of a digital recession came when the US property market crashed, says Anshe Chung, a virtual property developer and the first person to make a million real dollars in the online world Second Life. "People became more reluctant to invest in virtual real estate," she says. "More expensive, larger land holdings became less sought after, leading to a slowdown in growth in Second Life." By coincidence, Second Life's creator, Linden Lab, had already put into place its own version of quantitative easing. Rather than printing more virtual money, Linden Lab created more virtual land and cut the cost of developing it. The effect of this was to stabilise the market.
But while people have been spending less cash in virtual worlds, more people seem to be visiting them for longer. Whether rising unemployment in the real world means more people are spending more time online, or they are trying to save cash by staying in, more user hours are being clocked up in online worlds, says Chung. As a result, the Second Life property market is steadily recovering.
Recession could still spell trouble for the wider internet, though. Prior to 2006, global traffic steadily doubled year-on-year, says Andrew Odlyzko, who runs Minnesota Internet Traffic Studies at the University of Minnesota in Minneapolis. "But in the last few years we have seen a decline in that rate of growth." In fact, the rate of increase is now almost half 2006 levels.
With this reduced growth has come a reduction in the level of investment into infrastructure. Generally speaking, the internet can handle a 100 per cent surge - a doubling - in traffic at any one moment, Odlyzko says. If huge numbers of people suddenly turn to the internet to escape the recession, however, there is a chance that the rise in traffic will outpace the expansion of infrastructure, making internet outages increasingly likely.
Unknown internet 5: Is there only one internet?
Probably - for now. The internet is a disparate mix of interconnected computers, many of them on large networks run by universities, businesses and so on. What unites this network of networks are the communication languages known as the Transmission Control Protocol and the Internet Protocol, collectively TCP/IP.
There are also a few large networks that use different protocols and which remain largely isolated from the internet, including something called FidoNet, which links bulletin board systems via the global telephone network, as well as a handful of military networks. The main internet is the only one of any significant size, as far as we know.
Yet while a common computer language has proved a key to the internet's phenomenal success, another form of language - this time human - could eventually trigger its fragmentation into several separate regional internets. In 2007, under pressure from China and Russia, ICANN finally allowed the use of non-Latin characters in online addresses. The move will help billions of Chinese and Russian speakers use the internet, making communications easier and improving online trade within these countries. However, it could also prove to be the beginning of the end for the internet as we know it.
One possibility is that we could see the appearance of domain names that are not recognised by the rest of the network. If servers or routers aren't set up to recognise the characters in these addresses, the domain names will not be readily accessible from all parts of the world.
Worse will come if, say, the Chinese government decides to set up its own root directory of Chinese domain names, held on its own computers and independent of the existing US-based directory. This could give the Chinese authorities control over which sites its citizens access, potentially giving it the power to largely isolate them from the rest of the net. "The language changes will accelerate national fragmentation of the internet," warns Tim Wu, professor of technology and law at Columbia University in New York. He predicts this will lead us down a road towards a divided internet: one part controlled by the US, one by China, and another by Russia.
Unknown internet 6: Where are the net's dark corners?
There are plenty of places online that you would do well to steer clear of. A brief visit to some unsavoury websites, for instance, could leave your computer infected with worms or viruses. Then there are the "black holes" to worry about.
If your emails mysteriously disappear, or your favourite website is suddenly unobtainable, you might have run into one. Though nowhere near as destructive as their cosmological cousins, information black holes can create all kinds of problems for surfers. Essentially they are points on the network at which data packets simply disappear due to broken connections, say, or misconfigured routers - devices that maintain lists of addresses and which help direct internet traffic. A team including computer scientist Ethan Katz-Bassett at the University of Washington in Seattle has detected almost 1.5 million black holes since it began looking in 2007. The majority persist for over 2 hours, he says. Unfortunately it is tough to predict where they will appear next, so it's hard for the average surfer to avoid them.
Far easier to avoid are a kind of online chatroom called Internet Relay Chat channels. Though the majority are legitimate, a few IRC channels have a very dark reputation, and are run as open markets for stolen goods. One 2007 survey found $37 million worth of illegal stuff in IRC channels, including 80,000 credit card numbers and bank account details. And if that is not bad enough, some of these chatrooms are also used by hackers to send commands to their networks of malicious software bots, or botnets. When a PC is infected by a virus or malicious software it may be hijacked and used as part of a botnet to launch spam or cyber-attacks elsewhere.
Then there are significant pockets of cyberspace - some 5 per cent of all internet addresses - that are not fully connected to the rest of the net. Dubbed the "dark internet", they are often the result of faulty routers or networks with strict security policies that block traffic.
Amongst these dark regions are blocks of seemingly unused internet addresses that may suddenly and briefly flare into activity. Although this behaviour might have an innocent explanation, it can also hint at dubious activities.
A three-year study by online security consultants Arbor Networks revealed that dark internet addresses can be a source of cyber-attacks and junk email. The study suggests that hackers or spammers hijack routers and use them to create false addresses which are left dormant until the hackers bring them to life to facilitate their nefarious ends. These dark addresses seem to be multiplying in proportion to the growth of the net, says Arbor Networks' Craig Labovitz.
Could we shut the net down?
Almost certainly not. Much of the infrastructure - the servers, cabling and satellites, and the internet service providers (ISPs) that run them - is in private hands. A government might be able to mandate that ISPs in their territory be shut down, but people could still receive data through satellite links controlled by companies not answerable to that government. To extend that shutdown across national borders is barely conceivable. "One very powerful government could have strong effects on their own country, but it would be very difficult to do on a worldwide basis," says Milton Mueller of the international Internet Governance Project.
Mueller says he finds it hard to think of a reason why we might want to shut down the internet. Even the biggest cyber-attacks cause much less economic damage than closing the internet would. What's more, he points out, malicious attempts to disable the internet are testimony to the difficulty of the task: the biggest attack in history came in February 2007, and you probably didn't even notice.
This attack attempted to overwhelm the 13 "root name servers" that carry the directory of all the internet addresses in use worldwide - data vital to the smooth running of the net. Two servers, both in the US, were affected, but with 11 others untouched, the attack failed.
ICANN has now begun to implement a further safeguard system, known as Anycast, by which each of the internet's 13 root name servers also acts as a duplicate, or mirror, for some of the others. "A root server in California can be mirrored in Taiwan or the Middle East," Mueller says. "By playing tricks with the addressing, we effectively have hundreds of these root servers."
And if cyber-assaults get nowhere in shutting down the net, physical attacks on the infrastructure are unlikely to fare much better. You would have to plant bombs to destroy undersea cables, before launching missile attacks on the root name servers that are spread around the planet. "Then the internet will be the least of your worries," says Mueller. "We're talking about full-fledged war."
The internet is here to stay. Get used to it.
Is the net hurting the environment?
Sending an email across the Atlantic Ocean does not burn any jet fuel, but the internet is not without its own, huge carbon footprint. One estimate suggests it takes a whopping 152 billion kilowatt-hours per year just to power the data centres that keep the net running. Add to that the energy used by all the computers and peripherals linked to it and the whole thing could be responsible for as much as 2 per cent of all human-made CO2 emissions, putting it on a par with the aviation industry.
The way we use our computers also has an impact. According to Google, the production of the electricity needed for a single internet search generates 200 milligrams of CO2. This may not sound much, but it adds up: 1000 searches produce the same CO2 emissions as an average European car travelling 1 kilometre. Worse, internet traffic is currently growing at around 50 per cent each year. According to the international environmental coalition The Climate Group, total emissions from computers will increase by 280 per cent, to the equivalent of 1.4 gigatonnes of CO2, by 2020.
If the IT industry continues with business as usual, there is no question that the internet's energy consumption will skyrocket, says Bill Weihl, Google's green-energy tsar. As a result, many organisations are turning to so-called green data centres which are far more efficient at cooling computers. At the same time, new computers are becoming more efficient. This has led to the energy needed to send each megabyte of data across the net to fall by about 30 per cent annually, says Jonathan Koomey, an energy expert at the Lawrence Berkeley National Laboratory in Oakland, California.
IBM says it is developing carbon-neutral data centres, using a novel form of water cooling which channels the heat given off by chips to provide warmth for nearby homes and offices. In a similar vein, Google has patented the idea of sea-based floating data centres which use wave motion as a power source, while cold water sucked up from the deep ocean could cool the computer chips.
The internet itself could help us to reduce our energy consumption. Video conferencing is just one example, says Koomey. "Moving electrons is always better than moving atoms," he says. What no one knows, however, is whether the technology has led to any significant reduction in travel, or whether uptake in video conferencing has actually increased our CO2 emissions.