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In the first part of my speech, I will try to answer the question What is the Internet?. That question is rather difficult to answer because the Internet is so many things to so many different people. But what exactly is the Internet ? It's simply a series of computer networks linked together around the world, communicating almost all the time with one another. A single network of computers, is for example, all the computers linked together within our school building. The Internet consists of thousands of these networks communicating together, like a big net or web! University networks connected to government networks connected to business networks connected to private networks - this is the Internet! These computer networks are physically linked together with telephone, radio, cable lines or via satellite. Networks from other continents are interconnected by the large, intercontinental telephone and fibre optic communication lines that run below the ocean floor.
2.1 Size of the Internet
I think the next informative thing about the Internet is the size. Nobody knows for sure how big the Internet is, or how many networks are actually linked, but it is estimated that there are approximately thirty to thirty-eight million people that are ‘on-line,’ with sites on every continent, including Antarctica! New user sites are continually being added. In fact, the Internet has grown at an exponential rate since its beginning. It is the largest network of computers in the world and is growing at about ten percent per month. That means that at the current rate of growth, the Internet-users will double just ten months from today.
2.2 History and Property
Now I am going to speak about the history and who owns the Internet. The Internet was first started as an experiment by the United States Department of Defence in 1969. The United States military needed a system for its researchers to communicate and share programs with one another over their computers. The computer researchers of the US Department of Defence developed the first long-distance network of computers which was called ARPANET (Advanced Research Projects Agency - Network). Remote military sites were then ‘connected’ via telephone lines. Universities and scientists soon saw the advantage of long-distance networking, and began connecting with ARPANET. Businesses and private individuals then started connecting and eventually the network became known as the Internet. Today, no individual, no corporation and no government owns the Internet - it is owned, operated and maintained by all of those who use it.
3.1 Uniform Resource Locator
Before I get into the various TCP/IP-based Internet services, I want to explain URLs, or Uniform Resource Locators. These constitute the most common and efficient method of telling people about resources available via FTP, the World Wide Web, and other Internet services. A URL uniquely specifies the location of something on the Internet, using three main bits of information that you need in order to access any given object. First is the URL scheme, or the type of server making the object available - this could be an FTP, Gopher, or World Wide Web server. Second comes the address of the resource. Third and finally, there's the full path-name or identifier for the object. As a quick example, URLs (at least those for the Web) generally look something like this one (which points to the Microsoft Web server): http://www.microsoft.com/ . If it starts with http, use Netscape or some other Web browser to access this url. After the URL scheme comes a colon (:), which delimits the server type from what comes next. If two slashes (//) come next, they note that a machine name in the format of an IP address will follow, such as http://www.microsoft.com/. The last part of the URL is the specific information. With this information you're looking for the path to the directory of the file you desire. Directory names are separated from the machine name by a slash (/).
Perhaps the first step that many people have tried when using the Internet is E-mail. In theory, E-mail is an electronic message from a sender to a recipient, (or multiple recipients.) Some people say that an email message is the Internet equivalent of sending a fax. Compared to postal E-mail, (often called ‘snail-mail’ by Internet users), E-mail is probably much faster. But there are several problems with E-mail. In theory, messages can be sent back and forth immediately (usually within a few seconds), regardless of whether the message is sent to the next building or to the next continent. Nevertheless E-mail messages may sit in the recipient’s electronic mailbox for days or weeks until the user checks them. To be able to send an E-mail message, you must know the E-mail address of the person you want to send the message to. A person's E-mail address is constructed from the username they use to login to their provider and the computer's Internet host name. By combining the two with an @ sign between, them you have created that user's E-mail address .
3.3 World Wide Web
Now I am going to introduce some services of the Internet. I think it’s advantageous to start with the widely know service named WWW (which means World Wide Web). The World Wide Web makes up a very large percentage of the Internet. Nearly seventy percent of all information searches are handled through the World Wide Web. Information is quickly found in the World Wide Web through typing in key words. The key words are searched through different search engines, such as Infoseek and Lycos, or through search directories, such as Yahoo and Magellan. These search engines look for key words in their databases. The search results from the search engine are then listed and the user can choose from the titles found. WWW is often also simply mentioned as Web. Web Pages can include texts, pictures, sound-files, animation's, videos and so on. With the new language "Java", which is used for programming Web-pages, there are several more possibilities to design a Webpage. Most people, who are not as well informed about the Internet as you might be after this speech, think that the WWW is, besides E-mail, the only service in the Internet. But there are several other services which I will try to explain in the following:
3.4 File Transfer Protocol
The second service which can be used is FTP. FTP stands for File Transfer Protocol, and not surprisingly, it's only good for transferring files between machines. In the past, you could only use an FTP client to access files stored on FTP servers. Today enough additional services such as Gopher and the World Wide Web, have implemented the FTP protocols so that you can often FTP files no matter what service you are using. You can even FTP files via E-mail. If you access a FTP-Server with a regular FTP-Client, you see the files listed, as they are listed in a normal UNIX System. You can also navigate by using UNIX-Commands. Or you can use a graphical FTP-Client, which shows directory-information in Windows-Style.
The third service is called Usenet. This is split into over 30000 groups called Newsgroups. In each of them, people can post messages to the group-topic. Almost everything on Usenet is a discussion of some sort, although a few groups are devoted to regular information postings, with no discussion allowed. Of course, you can always ask your question, and you usually get an answer , even if it's the sort of question everyone asks. Common questions are called Frequently Asked Questions, or FAQs, and are collected in lists and posted regularly for newcomers. If you search for the Newsgoup of your interest, you will probably find it. For example, there are even some Newsgroups for collectors of butterflies.
3.6 Internet Relay Chat
IRC is the fourth service, which is a little like the Usenet - that makes it possible to hold live keyboard conversations with people around the world. It's a lot like an international CB radio - it even uses "channels." Type something on your computer and it's instantly echoed around the world to whoever is on the same channel with you. You can join in existing public group chats or set up your own. You can even create a private channel for yourself and as few as one or two other people. And just like on a CB radio, you can give yourself a unique "handle" or nickname. You can access over 20000 channels with different topics. For example, if you are interested in cars, you can easily connect to the #cars channel and chat with many other people who are also interested in cars.
Telnet is a the last service and it is not easy to explain to people who have had no experience with a modem. The best definition for Telnet, I think, is that Telnet is like a normal ANSI modem-connection through the Internet. As with a standard modem, Telnet enables your computer to communicate with another computer somewhere else. As you give your modem a phone number to dial, you give Telnet an Internet address to connect to. And just like a modem, you don't really do anything else within Telnet itself, other than make the connection. In the vernacular, you say you "Telnet" to that remote computer. Once that connection is made, you're using the remote computer over the Internet just as you were sitting next to it. This process is unique because it enables me , for example, to Telnet any University in America (which probably runs a Telnet-Server) and use their Telnet-Server just as I did when I was actually there, and not 10,000 kms away in Austria.
4 GET STARTED
4.1 How to connect to the Internet
Now I am going to explain how it is possible for you to connect to the Internet. For you and most people using a microcomputer such as a PC, a modem generally makes the necessary link to the Internet. Modem stands for modulator-demodulator, and it enables your computer to monopolise your phone. The fastest modem in commercial use today can process about 56 kilobits per second. A few years ago, the fastest modem available could only process 300 bits of information per second. Nowadays, new connection methods like ISDN (Integrated Service Digital Network) are upcoming. ISDN lines can process information at 128 kilobits per second. The ISDN lines would be installed in place of telephone lines. Satellites are also used to transmit data to computers. Current satellites can process up to 400 kilobits per second.
4.2 The Future
But even the ISDN lines and satellites may be outdated before they are widely introduced. Even faster processing is being researched, using coaxial-based cable TV lines and special cable-data modems. These experimental modems using coaxial cable TV lines will be able to process information at over 27 megabits per second on the same cable lines that are already hooked up to your TV! Even "Telekabel Vienna" is operating to provide such a cabel-internet service. Most researchers predict that the way to high speed connections in the future is through cable lines, which are relatively inexpensive and easily linked with phone and video lines! Video and voice transmission is also not a future melody, some simple voice- and video-connections over the Internet are even possible for normal users. Some feel that even the personal computer will eventually become obsolete - in the next few decades. Research is being done to replace computers with an inexpensive terminal and a connection to the Internet. Larry Ellison, CEO (chief executive officer) of Oracle, and Scott McNealy, CEO of Sun Microsystems, believe that the personal computer is not necessary and that a large central computer with a high speed network system is all that is needed for all computer transmissions. This would eliminate the need for computer software, upgrades, and so on, since central computers would contain all the information and programs necessary for any computer application. The Internet would simply be installed at main computer sites, and each person could access it by connecting their special monitor to transmission lines. Recently, a prototype was introduced that is capable of all Internet capabilities, at the estimated price of around 300 US dollars!
Finally, I would like to say that the Internet brings us closer to the future, and that we must begin to use and expand its potential whenever possible. In just a few years, the Internet became a mass-medium. The Internet is now used by 36 million people and every month this number increases by 2 million. But with this mass of users, the Internet is also getting slower, because many millions of people are using the Internet at the same time. Because of this, new connection-methods like cable-account, are needed. Also the band-witdh of the wires between each servers has to get higher, so that an acceptable speed is provided. In the future we will be able to use the Internet for watching TV, listening to music, talking to each other via voicemails and do many other things which we could not imagine now.
An account is the access authorization for a provider.
The Advanced Research Projects Agency was founded in the USA. Its main purpose was to develop new technologies.
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