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
