Интернет (Internet)

Интернет (Internet)

Introduction.

One of the main differences of the Internet from all rest, that is

connected to computers, is that for successful work with it(him), generally

speaking, it is not necessary of any books. Internet can serve both

directory, and tutorial, and encyclopedia itself. However on the initial

stage, as it seems, the advantage(benefit) of the book, distinctly and is

accessible of a stating basis, can be rather significant. Such book I also

have tried to write. But before you will get acquainted to it(her) more

close, let's try to answer on the most important question, which, probably,

you already set to yourselves:

The Internet: that it, at last, such

More or less scientific definition of the Internet, which the books and

clauses on this subject are filled, certainly with, have the value. But the

most simple explanation suffices for our purposes while: the Internet is a

set of computers connected with each other by channels of

communication(connection), plus a set of standard rules, on which they

exchange by the information. Thus channels of communication(connection),

perhaps, even are less important, than rule of data transfer on them, named

in the Internet by the protocols. If even two computers cooperate on one of

such protocols is already present Internet.

The invention and the perfection of modems - special devices allowing the

computer to send the information on the phone, - has opened doors in the

Internet to huge quantity(amount) of the people, at which is not present.

Any special network equipment, and there is only personal computer and

telephone socket nearby.

Both Internet, and the modems for personal computers exist already rather

long. However only at all for a long time - about 1990 - the Internet has

typed(collected), at last critical weight of the users and resources

necessary for network revolution, occurring on our eyes. The high-speed

modems allowing the usual users of personal computers without restrictions

to enjoy by all boons of the Internet, have appeared even later. And the

system World Wide Web (WWW, or "«World wide web"), invented in 1993 and

former firstly only by one of many components of a network, has

borrowed(occupied) a leading position and began to define(determine) the

person of the Internet literally in last years - two. By and large, the

world Internet boom now in the heat - and very much was lucky(carried) to

you, that you were not late almost to the beginning of performance.

The Internet is, first of all huge set of computers and programs. Among

last you will find not only such, which are able well to decide(solve) your

concrete tasks, but also is greater such, whose abilities it will be

firstly complex(firstly difficult) even to present to you, probably. The

Internet connection gives you a unique opportunity, what imperfect was your

computer to have a look per the twenty first century and independently to

accustom with such concepts, as « world cyber – social », « virtual money

», « information environment(Wednesday) habitation». Item, - word, with all

of subjects, about what so love to write now journalists.

However it only part of the answer on a question « that such the Internet

». The Internet today is not only huge quantity(amount) of computers, but

also the improbable quantity(amount) of the people, for which network is an

essentially new way of dialogue almost not having of analogues in the

material world. The man - essence social, and dialogue with itself similar

- one of his(its) first needs(requirements). Perhaps, till now still any

technical invention (short of the telephone) does not make such revolution

in this ancient as the world employment(occupation) - dialogue of the man

with the man.

Certainly, what exactly will interest you in the Internet first of all -

people or computers, - depends only on you. The ancient metaphor of the

book as models of world, perhaps, deserves reconsideration - now on a role

of such model computer approaches much better. When the speech goes about

millions computers and their users all over the world, connected in a

uniform network, the metaphor this already ceases be simply metaphor. That

is why by exaggeration will not tell, that, leave in the Internet, you do

(make) for yourselves accessible the whole world.

1. Basic protocols in Internet and search in them.

Internet contains vast quantity (amount) of the information, on this in

it(him) it is difficult to find that that is necessary if not to know where

to search. The place of a presence(finding) (or address) each resource

defines(determines) it(him) URL. In URL the type of the protocol indicating

on what server contains the access is carried out: on WWW (on which

specifies recording: http), Gopher, ftp, telnet, or WAIS, it depends on

that what type of the information you will transfer. The network protocol -

set of the precisely certain rules: how to request, to make out and to send

on a network the given version of the information

telnet

Millions computers are joined(attached) to a network Internet and many from

them have interesting opportunities.

It appears, is quite feasible to reach these computers to look databases,

available in them, and programs. The special program telnet allows to

transform your computer into the client telnet for a data access and

programs in numerous servers telnet. For example researcher regularly can

work on several computers, which managers nominate to it(him) a special

name and password.

In itself telnet - the communication facility is simple; neither any of the

own interface, nor opportunities of search it(he) does not give.

Having contacted the help telnet with the removed machine and having

entered in a field of search the entrance name (login) and password

(password) you communicate with this machine and programs on further to

it(her), and telnet cares only of maintenance of communication(connection)

between you.

Certainly, many storehouses of the information, which were originally

served by the special programs with access on telnet now it is possible to

transfer(translate) on WWW, that not seldom and is done(made). However

there were also such which on former give the services only on telnet

(especially among the catalogues and information services of libraries).

Standard the link on telnet connection with some site Internet (i.e. URL-

the address of this connection) looks so:

telnet: // < the address of the server >

FTP

Practically information is stored(kept) in the computer world as files. On

this for itself заре Internet the special means for an exchange of files on

a network - network protocol FTP (File Transfer Protocol) has appeared.

The quantity(amount) of files accessible on sites of all world on anonymous

FTP is measured in astronomical figures and constantly grows. Besides Word

Wide Web allows without any alteration existing FTP of archives, to supply

with their descriptions of any degree of detail and convenient hypertext

interface.

But how to learn(find out) where to address in searches of the necessary

file?

Archie.

The search on a name of a file on all anonymous FTP-sites of the world can

be carried out with the help of system Archie. She(it) is developed by the

several programmers from university Magellan in Canada and carries out

indexation of stations FTP, showing files, accessible in everyone station.

Archie informs several millions files taking place in more thousand

stations FTP, and gives a surprisingly fast way of search of that place,

where it is necessary to be directed for reception of a file, interesting

for you. The search in a database of the server Archie is made with the

help of keywords, which in this case represent simply names of files or

fragments of names.

Now Archie is accessible through WWW. It WWW page with the form in which

the keywords and options of search are specified.

Though the name of a file almost always has a certain attitude(relation) to

his(its) contents, to use Archie for thematic search of the programs does

not cost. This system will be useful, if you really know a name of the

necessary file or part of a name. On the other hand if you search for the

program, which has the standard reduced name, that is some probability that

this reduction will be present and at a name of a file, so it is possible

to try to find such file with the help Archie. The results of search

represent the list of FTP-sites and complete names of files on these sites.

The name of a file serves the link to this file, so the click on a name

will allow at once receiving a file from the given site. And domes the

address of FTP-archive allocated by a large greasy font will transfer you

to the initial catalogue of file system on this archive.

Archie the list into the list into the list into the list into the

reception.

URL-address indicating FTP-connection, owes, as a minimum to include a word

“ftp” as the left part and address of the site in right:

ftp: // < the address of the server >.

WAIS

Almost all information resources Internet give an opportunity of automatic

search, but only in one of them - in system WAIS (Wide Area Information

Server, global information server) - the keyword search, is the basic

method of access to the information.

The system WAIS represents the huge distributed(allocated) database, i.e.

the separate parts of this database are located on different net points

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