Services and Resources of the Internet 


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Services and Resources of the Internet



A COMMON resource provided by the Internet is a worldwide system for sending and receiving electronic mail, known as E-mail. In fact, E-mail represents a large portion of all Internet traffic and is for many the only Internet resource they use. How does it work? To answer that question, let’s review the ordinary mail system first.

Imagine that you live in Canada and wish to send a letter to your daughter living in Paris. After properly addressing the envelope, you mail it, starting the letter’s journey. At a postal facility, the letter is routed to the next location, perhaps a regional or national distribution center, and then to a local post office near your daughter.

A similar process occurs with E-mail. After your letter is composed on your computer, you must specify an E-mail address that identifies your daughter. Once you send this electronic letter, it travels from your computer, often through a device called a modem, which connects your computer to the Internet via the telephone network. Off it goes, bound for various computers that act like local and national postal routing facilities. They have enough information to get the letter to a destination computer, where your daughter can retrieve it.

Unlike the regular mail, E-mail often reaches its destination, even on other continents, in minutes or less unless some part of the network is heavily congested or temporarily out of order. When your daughter inspects her electronic mailbox, she will discover your E-mail. The speed of E-mail and the ease with which it can be sent even to multiple recipients all over the world make it a popular form of communication.

Newsgroups

Another popular service is called Usenet. Usenet offers access to newsgroups for group discussions on specific topics. Some newsgroups focus on buying or selling various consumer items. There are thousands of newsgroups, and once a user has gained access to Usenet, there is no cost to subscribe to them.

Let’s imagine that someone has joined a newsgroup involved in stamp collecting. As new messages about this hobby are sent by others subscribing to this group, the messages become available to this newcomer. This person reviews not only what someone has sent to the newsgroup but also what others have written in response. If, for example, someone requests information about a particular stamp series, shortly afterward there may be many responses from around the world, offering information that would be immediately available to all who subscribe to this newsgroup.

A variation of this idea is the Bulletin Board System (BBS). BBSs are similar to Usenet, except that all files are located on a single computer, usually maintained by one person or group. The content of news-groups reflects the varied interests, viewpoints, and moral values of those who use them, so discretion is needed.

File Sharing and Topic Searching

One of the original Internet goals was global information sharing. The teacher mentioned in the previous article located another educator on the Internet who was willing to share already developed course materials. Within minutes the files were transferred, despite a 2,000-mile distance.

What help is available when one does not know where a subject may be located within the Internet? Just as we locate a phone number by using a telephone directory, a user may find locations of interest on the Internet by first gaining access to what are known as search sites. The user supplies a word or a phrase, the site then replies with a list of Internet locations where information can be found. Generally, the search is free and takes only a few seconds.

The farmer mentioned earlier had heard of a new technique called precision farming, which uses computers and satellite maps. By entering that phrase at a search site, he found the names of farmers who were using it as well as detailed information about the method.

The World Wide Web

The part of the Internet called World Wide Web (or Web) allows authors to use an old-fashioned idea that of footnotes in a new way. When an author of a magazine article or a book inserts a footnote symbol, we scan the bottom of the page and are possibly directed to another page or book. Authors of Internet computer documents can do essentially the same thing using a technique that will underline or highlight a word, a phrase, or an image in their document.

The highlighted word or image is a clue to the reader that an associated Internet resource, often another document, exists. This Internet document can be fetched and displayed immediately for the reader. The document may even be on a different computer and located in another country. David Peal, author of Access the Internet, notes that this technique «links you to actual documents, not just references to them»

The Web also supports the storage and retrieval, or playing, of photographs, graphics, animations, videos, and sounds. Loma, the housewife mentioned at the outset of the previous article, obtained and played a short colour movie of the current theories regarding the universe. She heard the narration through her computer’s audio system.

Surfing the Net

By using a Web browser, a person can easily and quickly view information and colourful graphics that may be stored on computers in many different countries. Using a Web browser can be similar in some ways to actual travel, only easier. One can visit the Web exhibits of the Dead Sea Scrolls or the Holocaust Memorial Museum.

This ability to move nimbly back and forth from one Internet Web site to another is commonly called surfing the Net.

Businesses and other organizations have become interested in the Web as a means to advertise their products or services as well as to offer other kinds of information. They create a Web page, a sort of electronic storefront window. Once an organization’s Web page address is known, potential customers can use a browser to go “shopping”, or information browsing. As in any marketplace, however, not all products, services, or information provided on the Internet are wholesome.

Researchers are trying to make the Internet secure enough for confidential and safeguarded transactions. Another worldwide Internet-dubbed by some Internet II – is being developed because of the increased traffic that this commercial activity has generated.

What Is “Chat”?

Another common service of the Internet is the Internet Relay Chat, or Chat. Chat allows a group of people, using aliases, to send messages to one another immediately. While used by a variety of age groups, it is especially popular among young people. Once connected, the user is brought into contact with a large number of other users from all around the world.

So-called chat rooms, or chat channels, are created that feature a particular theme, such as science fiction, movies, sports, or romance. All the messages typed within a chat room appear almost simultaneously on the computer screens of all participants for that chat room.

A chat room is much like a party of people mingling and talking at the same general time, except that all are typing short messages instead. Chat rooms are usually active 24 hours a day. Of course, Christians realize that the Bible principles about association, such as the one found at 1 Corinthians 15:33, apply to participation in chat groups just as they apply to all aspects of life.

Voice Telephony (VoIP)

VoIP stands for Voice over IP, where IP refers to the Internet Protocol that underlies all Internet communication. This phenomenon began as an optional two-way voice extension to some of the instant messaging systems that took off around the year 2000. In recent years many VoIP systems have become as easy to use and as convenient as a normal telephone. The benefit is that, as the Internet carries the actual voice traffic, VoIP can be free or cost much less than a normal telephone call, especially over long distances and especially for those with always-on Internet connections such as cable or ADSL.

Thus, VoIP is maturing into a viable alternative to traditional telephones. Interoperability between different providers has improved and the ability to call or receive a call from a traditional telephone is available. Simple, inexpensive VoIP modems are now available that eliminate the need for a PC. Voice quality can still vary from call to call but is often equal to and can even exceed that of traditional calls.

Remaining problems for VoIP include emergency telephone number dialing and reliability. Currently, a few VoIP providers provide an emergency service, but it is not universally available. Traditional phones are line-powered and operate during a power failure; VoIP does not do so without a backup power source for the electronics.

Most VoIP providers offer unlimited national calling, but the direction in VoIP is clearly toward global coverage with unlimited minutes for a low monthly fee.

VoIP has also become increasingly popular within the gaming world, as a form of communication between players. Popular gaming VoIP clients include Ventrilo and Teamspeak, and there are others available also. The PlayStation 3 and Xbox 360 also offer VoIP chat features.

 



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