How the World Wide Web Works
Imagine a restaurant that serves many hundreds of thousands of clients every day. Nobody knows how many clients there really are. It might be millions. Or even billions. They're everywhere.
None of the servers or clients ever meet each other face to face. All communication is through slots.
A client puts an order into a slot and gets an item out of the slot. Servers see an order arrive at a slot and respond by putting an item into the slot
It's a strange restaurant.
Every server has a number. And every request has to be addressed to a specific server.
When an order is put into a slot, it's sent along a pipe to a central routing station. The router determines which pipe the order should be shunted into so it arrives at the correct server.
It's an odd communication system. But it works. The servers receive the orders and the clients get their items.
Another odd thing: The servers will accept orders for only one item at a time.
Servers respond to orders by putting the ordered item into a packet.
When the packet is ready, it's put into a slot, which goes to a router, which routes it to the client who ordered the packet in the first place.
Clients who order from this restaurant are a bit strange. They don't mind ordering one thing at a time. If they want something that's composed of more than one item, they'll order it in pieces and put it together when the packets arrive.
So if a client wants mashed potatoes and gravy, two packets are ordered. When they arrive, the mashed potato packet is opened, then the gravy packet is poured over it. To make a meal, a packet of chicken breast strips and a packet of corn might be ordered. And maybe a packet of seasoning.
Later, if so desired, a dessert packet is ordered.
If you've ever wondered how far the idea of an ala carte restaurant can be taken, this is it.
The World Wide Web works very similar to that hypothetical restaurant.
The servers in the restaurant are computers running server software that have websites available for the clients.
The clients are web browsers.
The slots and pipes are the phone and cable lines, and the radio waves, that connect all servers to all clients -- through the routers.
The World Wide Web has many routers. If a router gets a request or packet that it can't send directly to its destination, it will send it to a router that can.
A client (browser software) requests a web page by addressing the request to a specific server. The request goes through the routers, arrives at the server, the server responds with a packet containing the web page's source code and, after going through the routers on the way back, the packet arrives at the computer where the browser is running.
The browser scans the source code to see if it needs anything else for a full meal. If yes, it requests individual packets of image files, sound files, CSS files, JavaScript files, and whatever else it needs to create the web page according to the instructions contained within the source code.
Some requests might be addressed to different servers. It doesn't matter. The client (browser) orders all the packets it needs to create the web page.
Once it has all the packets, the browser displays the web page in its window on your computer.
That's an overview of how the World Wide Web works.
Let's close with a few short paragraphs about the Internet.
The World Wide Web is a part of the Internet. In other words, the Internet includes the World Wide Web.
The World Wide Web is a network of computers that serve web pages or other content to browsers.
The Internet, on the other hand, includes such things as email, FTP, and usenet, in addition to the World Wide Web. The Internet is a super-network, connecting many smaller networks together, allowing all the networked computers to exchange information with each other.
Will Bontrager
