How the Internet Works

The internet is made up of physical components, such as routers and modems, and software that allows computers to be connected to each other. Most people have a modem in their house, which connects to an ISP (Internet service provider). The ISP is owned by the company that you have written your contract with (UPC, Sky, etc.) and then connects to larger networks still, making the internet a large group of interconnected networks.  The ISP allows your computer to connect with millions more across the planet. When you search for something online your internet server firstly finds the page you want and sends it to you in small individual pieces of about 1500 bytes long. This is known as a packet-switching network as the information is sent separately along different paths to reach the user.

http://computer.howstuffworks.com/internet/basics/internet.htm

Another method of connecting to the internet is by LAN (Local area network) which is more commonly used in workplaces. The difference with an LAN server is that every computer in the network is able to view requests before deciding if the info is for themselves. However an LAN server’s performance will experience lagging and slower performance if it receives too many requests during a short space of time.

For servers to be able to send the correct info to the right computer they need to know the computers address. The computer’s personal address is called an IP address and in 1983 the University of Wisconsin developed technology to automatically map text names to IP addresses. The server sends the information as HTML code (Hyper Text Mark-up Language) which a browser changes into info that is displayed on your screen.

Routers are physical machines that forward info to different computers, ensuring they go to the correct places. They come in different sizes with the largest routers dealing with data at the busiest points of the internet where they forward millions of data packets every second.  If a router receives too many requests in a short period of time it can cause the system to run slower or even crash!