Computer World. Матросова Т.А. - 19 стр.

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have a simplified view of the Internet–a global collection of many different types of
computers and computer networks that are linked together. Just as a telephone
enables you to talk to someone on the other side of the earth who also has a phone,
the Internet enables a person to sit at his computer and exchange information with
other computers and computer users anyplace in the world.
Some refer to the Internet as the information superhighway. Just as a road allows
travel through different areas of a country, so the Internet allows information to flow
through many different interconnected computer networks. As messages travel, each
network that is reached contains information that assists in connecting to the adjacent
network. The final destination may be in a different city or country.
Each network can «speak» with its neighbor network by means of a common set
of rules created by the Internet designers Worldwide, how many networks are
connected? Some estimates say over 30,000 According to recent surveys, these
networks connect over 10,000,000 computers and some 30,000,000 users throughout
the world. It is estimated that the number of connected computers is doubling each
year.
What can people locate on the Internet? It offers a rapidly growing collection of
information, with topics ranging from medicine to science and technology. It features
exhaustive material on the arts as well as research material for students and coverage
of recreation, entertainment, sports, shopping, and employment opportunities. The
Internet provides access to almanacs, dictionaries, encyclopedias, and maps.
There are, however, some disturbing aspects to consider. Can everything on the
Internet be regarded as wholesome? What services and resources does the Internet
offer? What precautions are in order? The following articles will discuss these
questions.
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.

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