How the Internet works
The Internet is a giant web with millions of cables spanning the ocean.  Imagine a thousand of computers linked up in a network (intranet).  Then that one server, or maybe many using a high capacity line to connect to a couple of other servers with massive subscribers. That is exactly what the Internet is.  What happens is that you connect to an ISP via a modem.  When you type in a web page, a packet (sought of like sending a letter) is sent to your ISP.  The address is translated to an IP address and then is routed (sent) to the destination other multiple stops (or hops).  Then they send a letter back.  Every computer on the Internet has an IP address.  It is in the form *.*.*.* (eg. 213.54.0.6).  It is completely unique and later, you will find out ways of taking advantage of them.  In Windoze, you can find yours out, by running winipcfg when you are connected to the internet. On most connections, it changes every time U connect but Make sure that you are checking your ip for the internet (usually PPP adapter) and not the one for your home network.  Now, you are probably wondering how to find out someone elses.  The answer is netstat.  Any computer that you are connected to including IRCs server, will show up as an IP address provided that you are connected to them.  Just type netstat to run it. I suggest that you read a book to learn about the internet. It helps a lot!  
The end connections are called ports.  Your computer opens ports to connect to another computers with open ports.  This is very helpful in hacking.  The connection protocol u use for the internet is TCP/IP

The most common protocol for connecting to sites (not during dialup) is the Http protocol.  It is used for web pages but isnt the most efficient protocol.  Http is over port 80.  A lot of downloads you do are from the Ftp (file transfer protocol) and is the most efficient protocol.  Ftp uses port 21.  The connections between computers using Ftp is most commonly a directory entry looking like a normal directory.  These are the main protocols you need to worry about at the moment.Later you will learn about telnet as well. 

The internet protocol you use is version V4, however, even though version 6 has been developed, it isn't the standard because many problems faced with the original internet protocol has been tackled, for example, SSL made the packets more secure.  However, version 6 is set to become the standard as it is more suited to broadband and general internet connections as the first internet protocol was developed for Liberies, not for transfering credit card details.  

Also, strangely enough there has been an internet protocol designed for space known as I2P (I squared P but I couldn't do the exponent) but you wont need to worry about it... At least not 4 a while.