The World Wide Web. One small step for cats, one giant leap for cat memes. The Web has revolutionized, well, everything. So has the Internet.
Despite how these words are used today, they are actually different things.
Bam. I just blew your mind. That will be five bucks.
So yes, the Web and the Internet are not the same thing. If they aren’t the same thing, what is the difference?
The Internet
While the Internet is massive, it is fairly simple conceptually. In networking, there are networks. For example, you likely have a home network that your devices all use. Networks allow the sharing of information – without them, we would be limited to physically moving things back and forth. Cat memes are heavy, so that simply will not do.
So networks allow us to communicate, that is nice. The problem is, we want to communicate to people outside our home. How can we connect to people outside our network? We cannot simply keep expanding our network everywhere. It wouldn’t be possible to manage anymore, and, let’s be honest, nobody wants you to run the Internet. You would screw it up.
The answer? We connect networks together.
The Internet is really just a combination of some networks. And by some networks, I mean millions upon millions of networks. It is basically a worldwide collection of networks. This allows information to travel from your house, across the continent, under the ocean, all the way to some place in Australia. Unless, of course, you live in Australia, in which case go stare at kangaroos or something.
To connect to the Internet, you need an ISP (Internet Service Provider). They are the ones that link your itty-bitty little home network to the Internet.
Where do the ISPs get Internet access from? As it turns out, there are basically ISPs for ISPs. These are called backbones. As with skeletal backbones (you know, that spine thingy), these backbones are necessary to support all the connecting parts. The more central a part of the Internet is, the more traffic flows through it. While your link to your ISP is likely 50 Mbps or less, central parts of the Internet use links that are 100 Gbps and higher. In a given second, many terabytes flow over the Internet.
Who controls the Internet backbones? It is a mix of governmental and commercial organizations. Much of the infrastructure is owned by world telecom companies, like AT&T in the United States. These backbones negotiate deals with ISPs and each other to route traffic through their respective networks. Furthermore, they have redundant connections so if one particular provider suffers outages, traffic is rerouted through another provider.
There are also many IXPs (Internet Exchange Point). These are infrastructure elements that bind regional providers together, like all the ISPs in a large city like New York. They are typically operated mutually by the providers, where they share the operating costs. IXPs are useful because they allow efficient and fast communication between regional providers, rather than each of them communicating through an upstream middleman.
The design of TCP/IP – the protocol of the Internet – is key to allowing this system to work. The Internet is a decentralized network made possible by cooperation. It isn’t under control by any one entity. Furthermore, it is packet-switched. This means that messages shared between computers – say, streaming video – is actually sent as many, many small packets of information that each contain a small portion of the total. Each of these packets can be routed individually through the network which makes it very flexible when certain paths through aren’t functioning.
How do we know that a particular packet should go to Australia? When it has a kangaroo picture, duh. Oh, that isn’t how it works? My bad.
Much like the mail system has addresses, the Internet has IP addresses. In this case, each computer has an IP address. Devices called routers are responsible for finding out which “direction” a packet should go, and forwarding it on to the next router. Traffic across the Internet “hops” across a number of routers. Each router only knows about the IP addresses that are near it. For example, your home router only knows how to reach your ISP, and nobody else. Clearly I am more popular than your home router, because I have, like, 5 friends on Facebook. The router at your ISP, on the other hand, knows how to reach every address in your city. Look at Mr. Popular over there, knowing everybody and stuff.
ISP routers aren’t know-it-alls, though. For example, an ISP router in Canada isn’t going to know addresses in South Korea. Where do we send the packet now? In this case, it keeps bubbling up to more centralized routers, each which knows more than the last. Eventually it will reach a router who knows where it should go, which will forward it on. It will then proceed to bubble down the chain to more localized routers until it eventually reaches the ISP router and home router on the other end. If you are sending traffic to somewhere else in the world, it may bubble up to the top to a backbone router, which will know where to send it.
The Web
The Web runs on top of the Internet. It provides a way to access and navigate pages of information located on servers by using hypertext – links, as we think of them today. The Web exists as a combination of HTML (HyperText Markup Language) and HTTP (HyperText Transfer Protocol). Web pages are created with HTML. These pages are sent from Web servers to your computer through HTTP. HTTP requests and responses are sent over the Internet, and contain HTML pages as data.
The Web has changed over time. Back in the beginning before it became popular – roughly 1990 – text-based browsers were used. Or, in other words, there were no pictures. Sorry, your cat memes are in another castle.
Eventually a browser called Mosaic came along in 1993 which could display pictures. While that was an improvement, it still wasn’t the modern Web.
The Web as it exists today has three cornerstone technologies, namely HTML, CSS, and Javascript. CSS enables most of the visual effects you see, and Javascript enables all dynamic behavior. This latter duo came along in 1996 and 1995, respectively.
These technologies have continued to be updated over time. For example, HTML5 was a significant update for all three of these technologies. The HTML5 specification draft was released in 2008. Implementation began at that time and is still underway, though the popular browsers support the majority of it at present.
Browsers have changed as well. Simple things like tabbed Web browsing – a feature in every popular Web browser – weren’t always around. While the concept of tabbed browsing existed as early as 1994, it only reached the mainstream with Internet Explorer 7, released in 2006. Similarly, favicons (the picture you see next to each tab) began to appear in 1999, and even then they were used for favorites (bookmarks), not tabs.
How the Web is used has changed as well. Back when the Web began, pages were static – there was no interaction. This was changed with Web 2.0. Web 2.0 isn’t a technical change, but rather a buzzword for several changes in websites that were observed starting around 2000. The primary change was that websites began to incorporate user content – this includes concepts such as Facebook, Twitter, blogging, forums, comments, and so on. In other words, the Web as it is today.
The key thing about the Web is its ubiquity. The Web is the way to share information. There are other ways of sharing information over the Internet – IRC, for example – but they don’t share the Web’s ubiquity. There is a strong network effect here. The dot-com boom is a good example. Companies made websites because there were people using the Web. People used the Web because companies were on the Web. This resulted in incredibly fast expansion of the Web and Internet use.
The network effect is what made the Web different than similar concepts. If you want to share information over the Internet, there needs to be a way for users to access it. A company could, for example, make their own browser program that used their own information-sharing mechanism. The problem is that it would only work for that site. With the Web, there is one clear way to access information that everybody has the ability to use, so organizations can create websites knowing people will use them.
The Web is kind of like penicillin – a very beneficial, yet accidental, discovery, the implications of which were not initially clear.
The Difference
As noted in the Web section, the Web is ubiquitous. The primary way most people use the Internet is to use the Web. This is why the terms got confused and interchanged. Still, they are distinct things. Analogy time.
The Internet is like the interstate highway system. It provides the paths upon which traffic moves from one place to another. Its creation enabled widespread traffic that was not previously possible.
The Web is like the truck shipping industry. The trucks travel on the interstate, and compose much of its traffic.
The interstate doesn’t know nor care what uses it, it serves all types of traffic equally. The shipping is a specific type of traffic on the interstate that composes most of the traffic, and it is the most common use of the interstate.
But the interstate is not shipping, and shipping is not the interstate.
And, of course, the Internet is not the Web, and the Web is not the Internet.