ECM105: Introduction to the Internet

Course Documents


Unit 1 Part II
Unit 1 Part III

Introduction to the Internet - Part I



Let me say right up front that most computer-savvy people use the terms "Internet" and "Web" and "Net" interchangably. Knowing that, you won't get confused when people switch from talking about the Net to talking about the Web---they mean the same thing, in conversation.

But are they the same thing, really? Yes and no. The Web and the Internet depend on each other, but they're two different parts of a united whole.

The Internet is a huge network comprised of over 2.7 million computers around the world (as of January 12, 1999, and the number is growing every day!). These computers, termed servers---the computerese term for a place where information is stored---are all connected by telelphone cables and microwave and satellite to form a worldwide linkage. Everything you see on your screen is stored on one of those worldwide computers. It really doesn't matter where in the world it is, because using one storage place is just like another. That's the point of the Net!

Usually you buy your Internet access service from a provider called an ISP or Host. There are over 43.8 million of those worldwide, so obviously one or two of those share computer servers. We'll talk more about ISPs in Unit 2.

OK, you ask, so then what is the World Wide Web? Well, the Web is the information that you access over the Internet. In simple terms, the Internet is the hardware, and the Web is the software and data. So you can see how they depend on each other. The Web wouldn't be useful to us without the Internet's worldwide network backbone to allow us to access the information, and the Internet would just be a collection of computers and wires without the Web to give it life!

The Internet is a network of networks. It has no center, no overall authority and is modular, so that parts may be added or removed without impacting on the rest.

The one common denominator is a data transfer protocol - TCP/IP - which permits different kinds of computer with various operating systems to talk to one another. The Internet may be characterized as being technically complex and functionally simple. For instance, of ten messages sent one after another from, say, London to Tokyo, none may follow the same route. The actual route followed is neither determined by, nor probably of interest to, sender or recipient.

How many people use the Internet?

As of August 1998, it was estimated that 160 million people worldwide use the Internet. Of those 160 million users, some 54% are located in the US. Internet usage in the US has grown over 340% since 1995 alone.

History

How did the Internet develop? I'll bet it seems as if the Internet just appeared one day, a few years ago. But the truth is, it all started back in the 1960s when the US Department of Defense (DOD) became very concerned about the possible effects of a nuclear attack on its computing facilities. The DOD wanted all the large mainframe computers in the US and in military installations worldwide to connect to each other in a way that would not be harmed in the event of war. They charged an agency called the Advanced Research Projects Agency (ARPA, sometimes called DARPA) with making that connection happen.

ARPANET went online in 1969, and by the late 1970s (when your author started using it at UC Berkeley) the government, the military and large academic institutions were all using ARPANET at least for email. There were several more steps in between, but that was the result. As time went on, data was shared among the computers on ARPANET, so that in the event of the destruction of one computer no data would be lost.

Until around 1990 the government, the military and academic institutions were about the only ones utilizing ARPANET, because it was text-based and very hard, or at least tedious, to use.

Please click on the link above called Introduction Part II to continue with this unit.

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