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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

worldwide. The program - client for work with servers WAIS not only is able

to communicate with them under the special protocol, but also stores(keeps)

the list of all databases WAIS with their addresses and names, and

sometimes and with the brief descriptions. There it is possible to find

archives of news, every possible catalogues, directories, collections of

scientific clauses and abstracts, indexes and much another. Practically any

information, for which the database is the convenient form by performances

which is interesting enough to a wide audience, can be submitted in WAIS.

The database WAIS is so great, that idle time of recordings - extremely

unpromising way of access to the information. Therefore in WAIS the rather

complex(difficult) method of keyword search and phrases is applied. The

documents received as a result of search, are sorted by the WAIS-server by

quantity(amount) of entry in them of keywords and on, as far as is complete

in each of them all set of the ordered keywords is submitted. Such system

is capable to give good results, is especial if to break process of search

at some stages.

The first stage of search usually is the search special in a database under

the name “directory-of-servers”, which contains small on volume of the

description (abstracts) of all other bases WAIS. Thus it is better to

specify not those keywords, which at the end interest you, and those

general(common) concepts concerning your field of knowledge.

Having chosen on the first stage of one or several bases, it is possible to

begin search actually of documents - that also it is possible to do(make)

in some calls, getting acquainted after each search with results and

changing the list of keywords, the necessary document will not be found

yet. Besides WAIS has one useful property: if at the next stage of search

you have found the document, which contents are especially close that you

search, it(he) can be added to the list of the relevant documents. In

result at the following stage WAIS will find the documents, not only

containing a set of your keywords, but also similar on the dictionary

structure on those texts, which you have specified as most suitable.

Though Netscape is capable to work with servers WAIS, for this purpose

it(he) should know the address of the special proxy for the protocol WAIS,

of which your provider can not appear. The special WAIS-clients working

including under Windows, not only convenient for interactive search in

databases, but also allows to manage services any of the server –

intermediary.

URL-address for WAIS looks as:

wais: // < the address of the server > / < the name of base >

Gopher

Each of the considered till now Internet protocols quite could exist in

itself: telnet gives access to the programs, FTP - to files, WAIS - to

databases. All these systems were created both developed almost

independently from each other and put before itself the concrete purpose -

to construct the mechanism of access to one certain kind of resources.

However as Internet of dews also became complicated, it(he) pushed the

people to an idea, that the information on a nature is uniform and what not

too reasonably to divide her(it) on different “ kinds of resources ” with

unlike methods of access. By the end of 80-s' years the idea of a new

universal remedy of work with the diverse information was carried in air.

The first system called to embody for life these dreams began Gopher,

appeared on light 1991 at the American university of state Minnesota.

Fundamental concept incorporated in its(her) basis was structure enclosed

each other menu.

Having communicated Gopher- by the client with one of Gopher-servers, you

first of all get in the root, main menu of this server. Having oriented in

his(its) contents and passing further from one submenu in another, it is

possible to engage actually in search of the information. The information

in system Gopher is organized strictly hierarchically, “from the general to

the particular”. On each step the server sends yours Gopher - client not

only contents of the next menu, but also service information on, where

there are objects appropriate to items it the menu. The client deduces on

the screen only transfer of items, but when you choose one from them,

it(he), having verified with the information, available at him(it), or will

send on any of Gopher - servers search about distribution of the following

of the menu, or will try to establish FTP- or telnet- connection with some

site Internet.

Obviously from all information tools Internet Gopher most of all is similar

on WWW - both these systems are called to serve the shell with diverse

resources. However Gopher is deprived of those rich representational means,

which do(make) WWW not only information catalogue, but also new mass media

and even by a new genre of art. It is possible to tell, that Gopher is

“subset” WWW - that very much simplifies integration itself Gopher as one

of kinds of resources in WWW. Practically all that is told about work with

Gopher - by the client fairly and for travel on system Gopher with the help

of a browser WWW.

URL of one the menu consists of items Gopher - from addresses Gopher- of

the server and listed those items of the menu, which will result you in

initial item:

gopher: // < the address of the server > / < item of the menu >

WWW

In spite of the fact that per the first years of the existence Gopher has

won the large popularity, the need in any became ripe more simple and in

too time to maximum universal system, in which communication(connection)

between resources would be more free and associative. Such system was

developed in 1993 and is named World Wide Web (WWW). System WWW to be under

construction on concept of a hypertext, or, is exacter than hypermedia. The

hypertext is a text of which component are connected with each other and to

other texts with the help of the links. The hypermedia is that that will

turn out from a hypertext if to replace in his(its) definition a word

“text” on “ any kinds of the information ”: the graphic images, video,

sound etc.

World Wide Web “world wide web” means literally. Why she(it) so refers to

as. As it is clear from the name, she(it) is global. You not always know in

what part of light there is a computer, to which you are connected. You can

begin to read page Web in Dallas, then to proceed(pass) in Australia, and

all this on one pressing of the button of the mouse. WWW is similar to a

web. It is a complex(difficult) information network connected hypermedia by

communications(connections). WWW allows to not refuse information resources

already saved in Internet, other means, accessible with the help, - FTP,

telnet and Gopher. It is more than that, the work with these resources

through WWW is so convenient, that, say, FTP-clients, former at one time by

separate class of the programs, now are used only by few.

And nevertheless main in World Wide Web is not convenience of access to FTP-

of archive and Gopher-menu. The majority of servers of system WWW offer

the information, which without WWW hardly in general when or would get in a

network. Speed of creation and updating, the rich representational

opportunities in a combination to ease of access and huge audience have

made WWW by new mass media. The start WWW-servers and creation of WWW-pages

already has turned of a style to new business - with all that is peculiar

to modern business: by a payment for square centimeters of the advertising

area.

On the other hand, the fast distribution of system so naturally uniting

diverse resources, was promoted not in the last instance by its(her) origin

not in недрах of a business concern, and in scientific establishment -

European laboratory of physics of particles, which employees did not begin

to do(make) of secrets of the development and have not tried at all on

it(her) to grow rich.

Fortunately, nature WWW as first of all means of search and organization of

the information allows to hope, that this remarkable invention to not turn

to the tool of only one commerce and advertising.

The servers and clients WWW communicate among themselves under the special

protocol HTTP (Hyper Transfer Protocol, hypertext transfer protocol). URL

for WWW looks as:

http: // < the address of the server >

To pass from one page Web to another - an interesting way of research World

Wide Web, however you early or late need to find something concrete. But

thus it to make it will be not possible. In Internet there are special

tools of Web-search.

Tools of search in WWW.

Tools of search of the information in Internet, constructed on different

principles and pursuing the different purpose, exists much. But all unites

them that they settle down on the specially allocated network computers

with powerful channels of communication(connection), serve every minute

huge quantity(amount) of the visitors and require(demand) of the owners of

significant expenses on support and updating. Nevertheless, almost all of

them respond on searches of the users completely бескорыстно, and the

sponsors and advertisers pay for this pleasure. On scales of influence on

network community of retrieval systems, undoubtedly, are one of corner

stones Internet.

The classification of retrieval systems is more convenient for building all

on the basis of on the tax and processing of the information given to the

users, - or else how many is automated in them, who types(collects) a

database, in which the search is made: the people or computers.

2. Tools of search

Conditionally tools of search are subdivided into search means of a help

type (directories) and retrieval systems in the pure state (search

engines).

2.1 Thematic catalogues

The search tools of the first type name subject, or thematic catalogues

more often. The company owning such catalogue, continuously conducts huge

work, investigating, describing, cataloguing and displaying on half-glasses

contents of WWW-servers and other network resources scattered worldwide.

Result her(it) titanium of efforts is the constantly updated hierarchical

catalogue, at the top level the most general(common) categories, such as

“business” are assembled, "”science", "”art" etc., and the elements of the

lowermost level represent the links to separate WWW-pages and server

together with the brief description of their contents.

Guarantees that such catalogue really covers all contents WWW, nobody will

give, however possible(probable) not the completeness and selection of

materials is with interest expiated there, that for the present not under

force to any computer - intelligence of selection.

The subject catalogues give also opportunity of keyword search. However

search this occurs not in contents of WWW-servers, and in their brief

descriptions stored(kept) in the catalogue.

The subject catalogues Internet can be counted literally on fingers, as

their creation and support require(demand) huge expenses. To most known

concern Yahoo, WWW Virtual Library, Galaxy and some other.

Yahoo.

Is most popular in the population Internet the catalogue Yahoo. On the

first page Yahoo, located to the address http://www.yahoo.com, you receive

access to two basic method of work with the catalogue - keyword search and

hierarchical tree of sections.

Having begun descent(release) on sections of the catalogue, you will see,

that each section contains the precisely same field for input of keywords

and button Search, starting search.

Each section can include as transfer included in him(it) and actually links

to pages concerning at once all section, with their brief descriptions.

Instead of travel you can at once get in the necessary place of the

catalogue Yahoo with the help of search. Having entered one or several

keywords divided(shared) by blanks, in a line of search and having pressed

the button Search, you receive the list all in Yahoo, that comprises the

specified keywords. This list will be divided(shared) into two parts -

“categories” and “sites”.

If total of the links returned as a result of search, exceeds 25, the list

of the links will be broken on some parts.

Magellan.

But not seldom happens so, that the list, given out by the machine, is very

great and to see (overlook) it(him) simply not really. An output(exit) from

this situation can become stricter selection of the information brought in

the catalogue. One of most known such systems - catalogue Magellan to the

address: http: // www.mckinley.com

This database contains the items of information on 80 thousand WWW-pages -

that very much not much in comparison with those in millions, which exist

in a network. However if Yahoo as the description of a resource uses one -

two lines of the text, the employees of system Magellan on some of pages

brought in their database, write the small reviews, and also estimate

quality of these information resources on a five-mark scale. Till past

bases of the reviews, Magellan owns as an own automatic index, for search

in which it is necessary to throw the switch under a field of input in a

rule(situation) entire database.

As a rule search represents one or several keywords divided(shared) by

blanks.

Point.

The service, similar by the principles, of firm Point (http: //

www.pointcom.com) in general basic emphasis does(makes) not on search, and

on work with the thematic catalogue.

The service Point is known in a network for that its(her) employees are

constantly engaged оцениванием of network resources and conduct the lists

of those sites, which they consider(count) belong to “ to the best five

percents(interests) WWW ”.

Firm Point Conducts a shared database all “ of five-percentage WWW-pages,

where about everyone it is possible to read the detailed license.

Virtual Library.

The most old subject catalogue WWW is the catalogue Virtual Library:

http: // www.w3.org/hypertext/DataSources/bySubj ect/Overview.html

This system full enough covers a scientific layer WWW - servers of

universities, laboratories and educational institutions.

Russia-On-Line Subject Guide.

For the users in our country the certain interest can represent the

thematic catalogue Russia-On-Line Subject Guide, located to the address

http://www.online.ru/rmain. This catalogue contains rather motley assembly

of the links on foreign sources plus the thematic review of the Russian and

Russian resources WWW.

2.2. Automatic indexes.

It is possible to approach to a problem of search of the information in

Internet and on the other hand. There are programs in which have loaded

some thousand well-known URL-addresses. Being is started on the computer

with access to WWW, this program begins automatically to download from a

network the documents on it URL, and from each new document she(it) takes

all links, contained in it,(him,) and adds them in the base of addresses.

As at the end all WWW the documents are connected among themselves, early

or late such program will bypass all Internet.

Certainly, the program can not understand as or classify that she(it) sees

in a network. The programs of such type refer to as robots. They are

limited to the tax of the statistical information and construction indexes

in the texts of the documents. The database, collected by the robot, -

index - stores (keeps) in it, simply speaking, item of information on that

in what WWW-documents to contain those or other words.

Such the automatically collected index also underlies retrieval systems of

the second sort, which frequently and name - automatic indexes.

The automatic index consists of three parts: the program - robot collected

by this robot of a database and the interface for search in this base, with

which the user works. All these components quite can function without

intervention of the man.

As any classification of materials in such systems are absent, it is

necessary to resort to them only then, when you precisely know keywords

concerning that it is necessary, - we shall tell, a surname of the man or

it is enough some of rare terms from the appropriate area. If to set search

on the a little widespread words, you will have not enough life to bypass

all URL-addresses, received as a result of search, - for example, the index

of system Alta Vista contains of 11 billions words taken from 30 millions

of WWW-pages.

An automatic index of WWW-pages exists much: WebCrawler, Lycos, Excite,

Inktomi, Open Text and others. Some of them (for example, Lycos) represent

more or less successful synthesis of the subject catalogue and automatic

index.

Alta Vista.

Its(her) address http://altavista.digital.com. This system has appeared in

December 1995. She (it) one of largest on volume of indexes from all such

retrieval systems both most powerful and floppy rules of construction of

searches. Alta Vista understands two different languages of searches rather

strongly distinguished from each other. On the first page Alta Vista you

see the form for simple search (Simple Search), and the panel of heading at

the top of page contains the button Advanced Search, having pressed which,

you receive the form for complication of search.

Except for WWW-pages, Alta Vista conducts a separate index for clauses from

more than 14000 conferences Usenet (including hierarchy of groups relcom.

*).

Search Alta Vista: that Alta Vista worked on group of words, only when they

cost(stand) beside, it is necessary to conclude this group in inverted

commas. If it is necessary to exclude from result all documents containing

a certain word, it is necessary to attribute this word with is familiar

“minus”.

The word without any mark works in search precisely the same as also it

with is familiar “plus”.

As against Yahoo, by default Alta Vista searches of entry of the whole

words. The ordered terms should stand in the document separately, instead

of to be a part of other chains of symbols. If you need to find of all

entry of a word, even when it is included into structure of other words,

use a symbol *. The asterisk can stand only at the end of a word, and

prevent giving many (too much) of results, Alta Vista requires(demands),

that the word which is coming to an end on *, should consist not less than

of 3 letters. Moreover, a symbol * allows to find not any termination

(ending) of a word, but only not exceeding length of five symbols and not

containing of capital letters or figures.

Results of search Alta Vista, as well as Yahoo, gives out as the list of

the links on the documents, but instead of the description of each document

near to his(its) heading you will see simply first some lines of his(its)

text. If will be found more than 10 documents, Alta Vista will break their

list on pages till 10 links on everyone. Alta Vista sorts the links so that

on the first place there were “most important” documents with your keywords

at definition of a degree of importance taking into account the following

factors:

Whether the keywords into heading of the documents enter;

Whether these words in the first several lines of the documents contain;

As far as are close to each other in the text the keywords are found out.

Info seek

Info seek, entered in of operation at the end of 19996 years, is somewhat

reminiscent Alta Vista, however volume of the complete texts, surveyed by

him,(it,) of the documents yet does not exceed 30 million. Web-pages. The

address: http://www.infoseek.com. It is rather powerful system having high

speed and idle time in circulation. Opportunities of drawing up of search

almost same, as well as in Alta Vista, but not so rich. At almost complete

preservation of values of marks "«plus", "«minus" and "«inverted commas",

sensitivity to a difference header both lower case letters and opportunity

to limit search to fragments Web- of pages, Info seek yet has no ability to

define(determine) beside the worth terms (there is no operator NEAR), to

limit search by date of updating a source and, main, to truncate

terminations(ending) the key terms.

But the given retrieval system contains weight of facultative functions.,

for example, opportunity concerns to those to define(determine)

quantity(amount) of the links in WWW on concrete page, that is to judge, as

far as she(it) is popular or, on the contrary, to find out, how many links

to external pages contain on the given site, more correctly, how many from

them are reflected in index files Ultra seek. Use of special function Image

seek allows to find in Internet of the image (figures, photo) on the

certain subject. Info seek has also one of the best directories of

resources of a Network.

HotBot

By one of powerful search means in World Wide Web can attribute (relate)

HotBot, containing the items of information on the complete texts 110

million. Pages. The address: http://www.hotbot.com. HotBot belongs to the

newest systems, therefore his (its) profound search gives amazingly ample

opportunities for detailed elaboration of search. It is reached (achieved)

at the expense of use of the multistage menu offering various variants of

drawing up of the search instruction. It is possible to carry out search on

presence in the document one or several terms, search on a separate phase,

search of the concrete person or links to the certain electronic address.

For the greater detailed elaboration of search probably application of

conditions SHOULD (can contain), MUST (should necessarily contain), MUST

NOT (should not contain) in relation to any concepts. Besides HotBot

represents возможность ограничить search by date of creation or last

updating of the document, on geographic a rule(situation) of the server.

Top of service opportunities is the search of the documents containing

certain types of files, for example video. For this purpose it is necessary

only to make a mark in special item of the menu of search.

WebCrawler.

It is one more tool of search such as search-bot (search the robot).

The address: http: // www.webcrawler.com. The search here is very simple.

Enter maximal keywords into a field of search, press Search.

Lycos.

It is the large database that contents of all pages, found by Web.

The address: http://www.lycos.com.

World Wide Web Worm.

You will find this tool of search on

http://www.cs.colorado.edu/home/mcbryan/wwww.html. It is one more extensive

index of sites Web.

In each concrete case it is expedient to use the tool of search. You should

try to carry out(spend) search through one tool and, if you have not

received results, to pass to another. But nevertheless what tool to use?

First of all it is better to take advantage of the thematic catalogue such

as Yahoo, size at them rather small, but the speed is great. If to find the

necessary information it was not possible, it speaks that you are

interested in a too narrow subject, or badly correspond with your subject

the keywords, chosen by you. It does not mean, that the necessary

information in WWW is not present - it will be simple to find her(it) more

difficultly. For its(her) search to you will be reached to take advantage

of more primitive, more automatic and consequently by more universal

systems such as Alta Vista.

2.3. Russian retrieval systems

The retrieval systems of global scale concentrate the basic attention on

English resources of a Network. The task of search of the information on

servers within the limits of the separate countries is carried out with

systems of local character specially adapted for features of concrete

languages. There are similar search means and in Russia. All of them are

united by (with) an opportunity of processing of materials in all Cyrillic

codes*. However on capacity and level of offered service the Russian

retrieval systems considerably differ from each other.

Rambler, "Апорт" and "Яndex" now concern to leading group systems.

Rambler

Among favorites is allocated Rambler (http://www.rambler.ru), becoming with

the first professional domestic retrieval system. This system provides full

text search on 3 million. Pages located on more than 15 thousand Web sites

of Russia and the countries of near foreign countries. Besides Web-servers,

the week archive of news of hierarchy relcom is surveyed also.

Rambler has close to an optimum conclusion of results of search. Even in a

normal form the link on found object inserts the complete information. The

system is designed in such a manner that the same document in the various

coding is shown in the various coding are shown only once, and his(its)

concrete addresses are summarized in the list. it’s a reduces time on

analyze of the received results because of absence of duplication of the

same documents.

The main lack Rambler consists in impossibility to carry out search on the

whole phase or even to specify in searches limiting distance of the

required terms from each other. The casual combination of completely untied

words results in distribution of the links on the documents, are absolutely

not relevant to search.

Апорт

The retrieval system Апорт (http://www.апорт.ru) is supplied with weight of

various functions carrying her(it) number user-friendliest.

One consists of the main advantages Апорт in ample opportunities of drawing

up of search. Besides the traditional operators "both" and “or”, search on

the whole phase, the system is capable to isolate combinations of the terms

located in the text by a number (line) with each other. Апорт offers an

opportunity of machine translation of search with Russian on the English

language and on the contrary. Both Rambler, and Апорт are capable to

allocate the same document in the various coding and to give out the link

to him (it) only of time, listing(transferring) concrete addresses in the

list URL. Unfortunately, thus the items of information on the out-of-date

versions of the same page in time do not leave which are listed

(transferred) as existing, having a difference only in date of updating.

One more lack of this system is not always correct processing of the names

of pages, because of what as a result of search the document without the

name » frequently is underlined «.

Яndex

Retrieval system Яndex (http://www.yandex.ru), where besides servers of

domains «ru< and «su< Яndex индексирует the contents of foreign Russian Web-

sites.

The main distinctive feature of this system is the deep morphological

analysis of the process able terms. The most powerful linguistics allows to

take into account practically all possible (probable) shades of the use of

keywords and to make search maximum precisely. Яndex has the good mechanism

of recognition of one document in the several coding or on mirror servers.

After leading Russian тройкой there are some more search means, among which

“ the Russian machine of search ” (http://search.interrussia.com), "«TELA-

search" (http://tela.dux.ru/) and Russian Internet Search

(http://www.search.ru). While all these servers do not differ neither

breadth of search, nor by comfort, and can be used only as addition to

conducting search means.

The search service in the Russian block Internet, as well as all over the

world, develops promptly. There is no doubt, that in the near future

parameters of existing systems will be raised, the new generations of

search means giving to the users still (even) the large opportunities will

appear.



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