What would happen to the World Wide Web if humans suddenly disappeared from Earth?
In the very first moment, the only unusual thing would be lack of any human-generated "movement" in the Web. No tweets, no new posts on Facebook.
Then, this is how I see it:
- Within hours great improvement in bandwidth would be noticeable. Power plants that use coal (or other fuel that is being burned) wouldn't produce power anymore, so probably alternative power sources would be automaticly activated (coal power plants produce more or less 40% of electricity). If a building where the server is placed has no emergency power supply, the hosted site would go down.
- Within a few days backup accumulators in nuclear power plants would would be out of power. Control rods would automatically fall into reactor to stop the reaction. No more nuclear power. Next sites goes down, as some regions are stripped of electricity. Meanwhile, emergency power supply also goes down, due to empty batteries. Next servers are disconnected from the World Wide Web.
- Within a few weeks all power sources that reqire engineers to operate does not produce energy. Majority of cities and towns are simply out of power. And no power means no internet.
However there are still solar panels. Assuming that someone has a website hosted at home, which is running on electricity from solars placed somewhere on his roof, this website would be still operational.
So concluding, in this case World Wide Web is like a man left on a desert - it will die when it runs out of water. With this difference that some scraps of it could survive, and exist separately.
OK, there have been a few answers already, but they may not have painted a full picture.
What makes the Internet tick?
First, electrical power (obviously).
Second, as the name implies, the INTERNETwork is a network of networks: for it to work, the "backbone", the wide area networks provided by telephone and telecommunication companies, relying on a combination of fiber optic, conventional cable, terrestrial microwave and satellite links, must work.
Third, content providers, that is, servers where content is hosted, must operate.
If people suddenly disappeared, the electrical network in most parts of the world would break down rapidly. People (engineers, technicians) at electric power distribution centers still play an essential role responding to changing power needs, making critical decisions. In the absence of these decisions, parts of the network may overload (either because of excess demand or because of excess capacity), circuit breakers would trip, power stations would be disconnected, and cascading failures would bring down large segments of the networks. This very possibly could happen within minutes after people vanished from the Earth.
Critical telecommunications infrastructure has backup power (battery, generators) that kicks in automatically. So the backbone data network would continue to run in most parts of the world, possibly for days. Commercial grade server farms also have backup power, and at least some may be located near power stations, e.g., a hydroelectric dam. These, too, might continue to operate for a few days, perhaps even longer, even if they are no longer connected to the power grid as a whole. So 24 hours after people vanished, if you turned on a cell phone, there is a good chance that it would still find a working cell tower, and it would still have a connection to the Internet, and many of the well-known services, e.g., Google, would still be accessible.
But after a few days (at most), backup power will fail. Large parts of the backbone would go down. The Internet would no longer be an global internetwork anymore: it would collapse into fragments, some of which may stay up longer than others. But if you turned your cell phone on after a week, even if you are lucky enough to find a still working cell tower, chances are there is no cellular network anymore; and if there is one, your data connection will be useless, as you won't be able to access domain name servers that translate, e.g., google.com into the corresponding numeric IP address.
Ultimately, it's the lack of power that will kill the network. Utility power may stay on longer in some areas than others, some facilities may have backup power that lasts longer than elsewhere, but after a few weeks, tops, pretty much all of it will be gone.
Oh, you may still find occasional working facilities even years later. For instance, you may find a high tech office building with solar panels, with working Wi-Fi, and you may be able to access their own servers housed in the same building. Ultimately these, too, will fail as the batteries or energy storage systems that supply power, e.g., overnight, would fail. But even then, some facilities may continue to work intermittently, e.g., rebooting when the Sun is up. But these would be rare occurrences and eventually, even these would succumb: aging electronics, clogged fans, failing hard drives, leaky ceilings, you name it. After a few decades, I don't think anything will be left that's working.
But the Internet, or anything resembling a global network of networks, would be pretty much gone after the first few days, perhaps even the first few hours as parts of the critical backbone infrastructure fail.
The primary resource that drives the Internet is electricity, whether that is for the web servers in datacentres, the routers and switches that interconnect networks and are also generally housed in datacentres, or the mobile networks that connect your phone to the Internet. The electricity network is enormously complex, and requires active management to switch generators and other resources in and out. The electricity network would start breaking down fairly quickly, as circuit breakers trip and cause cascades of failures in the network. I'd expect that within a few hours most external power would have gone, leaving backup power only.
Datacentres have battery backup and diesel generators, which would kick in and would provide between 24 hours and several days of power. However, with no deliveries of diesel these would run out and the datacentres would shut down.
Cell towers often have backup power. Most only carry a few hours of reserve, so these would shut down first.
So I'd expect the Internet to carry on working from your phone for a few hours at most. If you could get into a datacentre you could access it for several days, but gradually more and more would disappear, and after 3 to 5 days, all would be silent.
No one would be browsing. So the server and network traffic would plummet - save for bots. Search engines and Google & Facebook services would lie fallow. Intelligent systems like these might automatically turn of whole swaths of datacenters.
All the web accounting infrastructure would lie fallow. Including all the cookie tracking infrastructure.
No one would be updating content and data - save automatically generated data from videocam feeds, sensors of various types, etc. No one would be updating code.
There would be no maintenance of computers, server and data center infrastructure, networks, Air conditioning, and the power grid.
Between a few minute to a few days most of the power grid would go offline - in fact this could happen in a few minutes since many powergens would shutdown due to lack of fuel being injected and the remainder of the overloaded power gens would automatically shutdown as this acenRio happened in the Northeast US about two decades ago.
Within a few months nature would start taking over all human structures, as witnessed after the Chernobyl nuclear crisis.
"(Hypothetical) What would happen to the World Wide Web if humans suddenly disappeared from Earth?"
Assuming you mean all humans disappeared with the exception of you, then events might unfold thus:
For a few hours or days, depending on the location of the data centers within the power grid, the Internet would hum right along, even though there is only one person to access it.
Soon though, generating stations would start failing. Not to worry immediately though, because most necessary links would have battery backup, some might even have auto-start generators. You on the other hand, likely do not. When your little piece of heaven on the electrical grid goes dark, it won't matter. Sooner or later, ( probably sooner) it will all fail.
So, if you need content that will enable you to survive, get online, go to all the needed websites that are still available, and print as fast as you can.
There would be an immediate improvement in bandwidth. But there would be no human interaction; just the content already appearing on and through the 'net.
Within a week, systems would begin to fail, and in a few more weeks, as electrical generation ceased operation, nothing at all requiring electrical service from the grid would work.
And thus it would be for the rest of your life, with humanity having taken its leave.