WHAT IS INTERNET?
A BRIEF HISTORY OF THE INTERNET
APPLICATION/SERVICES THAT ARE AVAILABLE ON THE INTERNET
UNDERSTANDING INTERNET ADDRESS
USING THE WORLD WIDE WEB (WWW)
SEARCHING FOR INFORMATION ON THE INTERNET
Computers and various other devices like printers and modems can be connected together to form a computer network. Computer network allows different computers to work together and to share devices like printer for example.
LAN stands for Local Area Network It means that "Local" computers and devices in the "Area" are connected and can communicate with each other. It normally covers a restricted geographical area like an office or a building.
As you have two or more computer networks connected together across a big geographical distance, you have a WAN (Wide Area Network). This allow the sharing of resources across huge distances like across cities or even states and countries.
Internet is a network system that connects up a huge number of computers and computer networks from around the world. There is a communication standard called TCP/IP that allows different computers to work together. It does not matter which brand or type of hardware or software that you are using, as long as they understand TCP/IP, they could make use of the Internet.
The Internet is growing at an exponential rate. Millions of people use it daily because it provides much benefits, convenience and value. The Internet is supported by most Universities, government bodies, private individuals, and major companies and thus it provides a wealth of information. One of the most important point of the Internet is information. people that are not connected to the Internet will not be able to access these vital information. Without Internet, they will communicate with their peers at a very slow pace. Even sending air-mail or "over-night delivery" is considered very slow when compared to sending e-mail via the Internet because the message could reach anywhere around the world within minutes and it cost less than the stamp that would be needed for postal service. Internet could also be considered as the largest library in the world, the amount of information is enormous and so is the range of information. On top of that, you could access it from the comfort of your own home.
A BRIEF HISTORY OF THE INTERNET.
ORIGIN OF THE INTERNET
During the early 1960s, American computer scientists were trying to connect computers at different locations to each other. In the late 60s the United States government slowly realize the impact computers would have on education and military research and development. This experiment was soon funded by the government as a military research project. The main aim of the project was to allow remote research and development sites to exchange information. The project resulted in a network called ARPANET.
ARPANET
ARPANET's main goal is to develop a network whose connections would not be broken if physical sections of the network were disconnected. The network must al so allow the insertion or removal of different types of computers from its network. The ARPANET project led to the development of the TCP/IP (Transmission Control Protocol/Internet Protocol) network protocol. TCP/IP is the language that computers connected to the network use to communicate with each other.
INTERNET TODAY
The government recognized the potential of the network and encourage the educational community to take advantage of ARPANET. This led to the slow but gradual growth of the Internet. The increasing number of users led ti the development of many of the services available on the Internet today (email, file transfer and remote login). In the early 1980s, all interconnected research networks were converted to TCP/IP protocol.
ARPANET, the physical connection between major sites was used to link all TCP/IP-based networks. This conversion process was finished in 1983 and the Internet was born.
During 1981, there were only 213 registered hosts (computers that provided services) connected to the network. In February of 1986 there were about 2,308 hosts connected to the network. Today there are several million hosts connected world wide, but this number is still growing.
The number of data packets (information transferred between computers) that flowed through NSFNET went from 152 million in July of 1988 to 60,587 million packets in July of 1994. The number of host (individual users that provide facilities to the Internet) on the Internet has grown from 235 in May of 1982 to about 3.2 million hosts in July of 1994. The majority of hosts are made up of educational and research organization. The commercial hosts now has about that same number.
Most people use the Internet to exchange information or to use remote computer resources unavailable to them.
Internet does not have any owner. The backbone in the U.S is funded by the National Science Foundation (NSF). It is technically supported by the Internet Engineering Task Force (IETF). IETF is a group of scientists that works to resolve technical and related support issues for the Internet.
Many sub networks of the Internet from other areas of the world administer and fund themselves. But all network connected to the Internet agrees to the standards set by the Internet Architecture Board (IAB).
APPLICATION/SERVICES THAT ARE AVAILABLE ON THE INTERNET
SERVICES THAT ARE AVAILABLE ON THE INTERNET
There are a few very useful services that the Internet provides which allows you to use Internet effectively. They are FTP (File Transfer Protocol), E-mail (Electronic Mail), newsgroups and WWW (World Wide Web) namely.
These applications allows you to manipulate or communicate information in different manner on the Internet. Some allows you to copy files from distance places while others allows you to send a message to a particular person on the Internet.
FTP (FILE TRANSFER PROTOCOL)
FTP is short for File Transfer Protocol. FTP basically allows you to enter or access another remote computer's hard drive. This remote computer system is connected to the Internet, and it is configured to allow others to access its file. Once you are in a particular FTP site, you can navigate around it's directories and access files of your interest.
FTP allows you to copy documents, programs, sound, pictures etc., from the Internet into your own hard disk. It is like having the Internet as a part of your computer hard disk.
When visiting FTP sites, one is required to specify userid and password. Many FTP sites nowadays allows " anonymous" to be entered as the userid. This allows the user to access the FTP sites without specifying the user's own name. The reason for the offering for this kind of open access is to encourage people to access their information and/or for case of maintenance.
E-MAIL (ELECTRONIC MAIL)
Similar to our existing postal mailing system, electronic mail allows us to send messages from one person to another on the Internet. E-mail message can contain anything from a few sentences to a few pages long. It allows anyone to quickly communicate across vast distance within a very short period of time. E-mail can be used to send important information about projects or products, or it can be used for private conversation with Internet friends. Another benefit of e-mail is that it is very cost effective. It is virtually free.
Before you send an e-mail to a particular person, you must know what his/her e-mail address is. An e-mail address is an address that will identifies a particular person. It is like a house or building address. However an e-mail address is the address of one particular person. E-mail addresses are unique for everyone. No two e-mail addresses will be the same. When an e-mail is sent to an e-mail address, only that person with that particular e-mail address will get the mail.
Some e-mail facilities allows the attachment of files. Thus with e-mail, you could also send pictures, audio, program, application files etc.
NEWSGROUPS
Internet newsgroups are on-line discussions (via posted messages) in the Internet about various topics. One can either read from or post an article to a newsgroup.
Newsgroups usually provides thousands of different topics. Each newsgroup is devoted to a particular topic. There is a newsgroup for almost every topic you can imagine (computer games, latest scores in the world cup, latest and hottest movies etc.).
One can imagine newsgroups as being a large building. In each room of the building will be a different newsgroup with its own unique topic. This room will have a name on its door and a brief description of the topic of its discussion. In some of these rooms, you can find various people discussing their related topics. If you are interested, you can join in their discussion, otherwise, you could just read what others have posted. This is just an abstract view of a newsgroup.
WWW (WORLD WIDE WEB)
A World Wide Web page is an Internet document that can contain graphic, photograph, logo, text, video image, and sound. From the user's point of view, a web is a collection of pages that can be viewed with a browsing tool from your desktop. From an author's point however the Web is a publishing mechanism. Thus, on the Internet everyone can be a reader or a publisher. Due to this reason, the Web is supported by a lot of people and it contains a lot of information.
At the moment, the World Wide Web have yet to be fully exploited. There is a continuous effort by interested parties to find out how to improve its ability and usefulness. There are many locations where user can do their shopping on the Internet and have their purchases delivered to their doorstep. It also supports non alphabetic based languages like Chinese and Japanese with the help of additional software.
WHAT IS A DOMAIN NAME?
A domain name is a unique identifier for your company that is used, for example, when mail is addressed to you. Domain names provide two pieces of information separated by a period : your company's online identifier or name and the type of company or organization you are. The later part, called the domain identifier, comes after the period. There are six domain identifiers established by the Network Information Center (NIC).
Here's the components of the Internet e-mail address:
aname@aserver.com
The three-letter suffix in the location name helps identify
the kind of organization operating the server. (Some locations use a two-letter
geographical suffix). Here are the common suffixes and organizational affiliation
:
URL stand for Uniform Resource Locator. It was developed to achieve the goal of the World Wide Web project to have a standard way of referencing an item.
A URL is a complete description of an item, containing the location of the item that you want to retrieve. The location of the item can range from a file on your local disk to a file on an Internet site half-way around the world.
A URL reference can be set up to be absolute or relative. An absolute reference contains the complete address of the document that is being referenced, including the host name, directory path, and file name. A relative reference assumes that the previous machine and directory path are being used, and just the file name (or possibly a sub directory and file name) are specified.
The URL is not limited to describing the location of WWW files. Many browsers can access a number of different Internet services, including anonymous FTP, Gopher, WAIS, UseNet news, and Telnet.
A typical URL would look like this:
http://www.eit.com/web/www.guide
The initial item in the URL (the part that ends with a colon) is the protocol that is being used to retrieve the item. A protocol is a set of instructions that defines how to use the particular Internet service. In this example, the protocol is HTTP, the Hypertext Transfer Protocol developed of the WWW project. The two slashes after the colon indicate that what follows is a valid Internet host address or symbolic location. It can be either the text as shown above, or the actual IP address of the site. In this URL, you want to find a file on that machine, so what follows after the host name is a UNIX style path for the file that you want to retrieve.
The URL in the prior example tells a WWW browser to retrieve the file www.guide from the /web directory on the Internet host www.eit.com, using the HTTP protocol.
Other protocols that WWW browsers can use to retrieve
documents are listed in the following table :
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
The World Wide Web (WWW or W3) is one of the newest Internet services. The WWW allows you to combine text, audio, graphics and even animation to make a document a learning experience. Links within WWW documents can take you quickly to other related documents. The speed of the Internet makes it easy to view a WWW document from halfway around the world.
The various WWW browsers allow you to explore WWW Internet sites, giving you quick access to hypermedia documents provided at those sites. Not only dose the WWW provide quick graphical access to hypermedia documents, but it also allows you to use the same GUI interface to other Internet services, such as FTP, Gopher, and UseNet newsgroups. The WWW is the closest the Internet has come to a comprehensive, user friendly interface.
HISTORY OF WWW
The history of the WWW is fairly short. In 1989, some researchers at CERN (The European Laboratory for Particle Physics) wanted to develop a better way to give widely dispersed research groups access to share information.
Over the course a year, the proposal for this project was refined, and work began on the implementation. By the end of 1990, the researchers at CERN had a text mode browser and a graphical browser for the next computer. During 1991, the WWW was released for general usage at CERN. Initially, access was restricted to hypertext and UseNet news articles. As the project advanced, interfaces to other Internet services were added (WAIS, anonymous FTP, Telnet and Gopher).
During 1992, CERN began publicizing the WWW project. People saw what a great idea it was, and began creating their own WWW servers to make their information available to the Internet. A few people also began working on WWW clients, designing easy-to-use interfaces to the WWW. By the end of 1993, browsers had been developed for many different computer systems, including X Windows, Apple Macintosh, and PC/Windows. By the summer of 1994, WWW had become one of the most popular ways to access Internet resources.
IMPORTANT WWW CONCEPTS
In reality, the WWW is constantly changing as Internet sites add or delete access to their information. Learning about some of the basic concepts of the WWW will help you understand the nature of the Web.
Browsers
To access the WWW, it is necessary that you run a WWW browser on
your computer. A browser is an application
that knows how to interpret and display that is finds on the WWW. Some
example of browsers are Netscape Navigator, Internet Explorer, Mosaic,
etc.
Hypertext (and Hypermedia)
When you use the WWW, the documents that you find will be hypertext documents. Hypertext is text that contains links to other text. This allow you to quickly access other related text from the text you are currently reading, The linked text might be within the document that you are currently reading, or it might be some where half way around the world.
In addition to text, many of the documents you retrieve may contain pictures, graphs, sounds, or even animation. Documents that contain more than just text are called hypermedia documents, because they contain multiple media.
HTML
When you retrieve a document from the WWW, the text that you read on-screen is a nicely formatted text. To do this, the documents that you read on the WWW cannot be plain text, or even text with specific formatting information in it (because the person who places a document on a WWW server doesn't know what type of computer or terminal is being used by the person reading the document).
To ensure that everyone sees documents displayed correctly on-screen, it is necessary to come up with a way to describe documents so that they are displayed in the best format for the viewing terminal or computer. The solution to this problem turned out to be HTML.
HTML (HyperText Markup Language) is used when writing a document that is to be displayed through the WWW.HTML is a fairly simple set of commands that describes how a document is structured. This type of markup language allows you to define the parts of the document, but not the formatting, so the browser that you run when reading the document can format it to best suit your display.
Link
One of the defining features of any hypertext documents is links (also known as hyperlinks). Links are simply references to other documents. They are actual live links, where you can activate the link and cause whatever it references to appear on your screen. When someone writes a hypertext document, he or she can insert links to other documents that have information relevant to the text in the document.
HTTP
One of the goals of the WWW project was to have documents that were easy to retrieve, no matter where they are reside. After it was decided to use hypertext as the standard format for WWW documents, a protocol that allowed these hypertext documents to be retrieved quickly was developed. This protocol is HTTP, the HyperText Transfer Protocol. HTTP is a fairly simple communications protocol that takes advantage of the fact that the documents it retrieves contain information about future links the user may reference.
Home Pages
All WWW users can set up their own home page, where they can set up links to sites that they use frequently. Home pages can also be developed for groups who use the same resources. For example, a project may need to set up a home page that gives links to all project related items that exist.
There are information that you want to floating around somewhere on the Internet. That's not to say that you will always be able to get to it. However, if it does exist in a computer somewhere, you probably could get to it through the Internet.
If you are at the beginning of an Internet information revolution, it's not always easy to find what you want or even to know how to find it. This lesson will teach you how to go about the Internet searching for information.
A LOOK AT SEARCH ENGINES
The World Wide Web is indexed through the use of search engines, which are also referred to as "spiders", "robots", "crawlers", or "worms". These engines comb through the Web documents, identifying text that is the basis for keyword searching.
Every search engine works in a different ways. Some engines scan for information in the title or header of the document. Others look at the bold "headings" on the page for their information. Search engines gather information differently means that each will probably yield different results. Therefore, it's wise ti try more that one search engine when doing Web searching.
There are couple of search engines that are popular on the Internet like Yahoo, Lycos, Magellan, Web Crawler, Alta-Vista and the list goes on.
HOW DO YOU DO A SEARCH WITH A SEARCH ENGINE
Searching the Internet is not like looking for telephone numbers in the phone book. Your phone number is given to you by your local service provider but information on the Internet is scattered all around.
There are many different Web databases, searched by many different search engines, not all databases contain the same information. A thorough Web search requires that you enter your search parameters using more than one search engine.
Below is an example of how to search the Internet:
1. Launch your Netscape browser.
2. Click on the Net Search button. A screen will appear
with a column where you can key in your keywords
3. Then you key in a keyword and click the search button.
4. A screen will appear displaying the results of your
search.
HOW TO BECOME AN INFORMED INTERNET SEARCHER
Searching networked resources on the Internet is a very useful way to supplement the research you've done using other sources. The following points should help you as you begin your search.
1. Don't ignore traditional channels or research