Реферат: Интернет (Internet)


One of the main differencesof the Internet from all rest, that is connected to computers, is that forsuccessful work with it(him), generally speaking, it is not necessary of anybooks. Internet can serve both directory, and tutorial, and encyclopediaitself. However on the initial stage, as it seems, the advantage(benefit) ofthe book, distinctly and is accessible of a stating basis, can be rathersignificant. Such book I also have tried to write. But before you will getacquainted to it(her) more close, let's try to answer on the most importantquestion, which, probably, you already set to yourselves:

The Internet: that it, atlast, such

More or less scientificdefinition of the Internet, which the books and clauses on this subject arefilled, certainly with, have the value. But the most simple explanationsuffices for our purposes while: the Internet is a set of computers connectedwith each other by channels of communication(connection), plus a set ofstandard rules, on which they exchange by the information. Thus channels ofcommunication(connection), perhaps, even are less important, than rule of datatransfer on them, named in the Internet by the protocols. If even two computerscooperate on one of such protocols is already present Internet.

The invention and theperfection of modems — special devices allowing the computer to send theinformation on the phone, — has opened doors in the Internet to hugequantity(amount) of the people, at which is not present. Any special networkequipment, and there is only personal computer and telephone socket nearby.

Both Internet, and themodems for personal computers exist already rather long. However only at allfor a long time — about 1990 — the Internet has typed(collected), at lastcritical weight of the users and resources necessary for network revolution,occurring on our eyes. The high-speed modems allowing the usual users ofpersonal computers without restrictions to enjoy by all boons of the Internet,have appeared even later. And the system World Wide Web (WWW, or "«Worldwide web"), invented in 1993 and former firstly only by one of manycomponents of a network, has borrowed(occupied) a leading position and began todefine(determine) the person of the Internet literally in last years — two. Byand large, the world Internet boom now in the heat — and very much was lucky(carried) to you, that you were not latealmost to the beginning of performance.

The Internet is, first ofall 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 greatersuch, whose abilities it will be firstly complex(firstly difficult) even topresent to you, probably. The Internet connection gives you a uniqueopportunity, what imperfect was your computer to have a look per the twentyfirst century and independently to accustom with such concepts, as « worldcyber – social  », « virtual money », «information environment(Wednesday) habitation». Item, — word, with all ofsubjects, about what so love to write now journalists.

However it only part of theanswer on a question « that such the Internet ». The Internet today is not onlyhuge quantity(amount) of computers, but also the improbable quantity(amount) ofthe people, for which network is an essentially new way of dialogue almost nothaving of analogues in the material world. The man — essence social, anddialogue with itself similar — one of his(its) first needs(requirements).Perhaps, till now still any technical invention (short of the telephone) doesnot make such revolution in this ancient as the world employment(occupation) — dialogue of the man with the man.

Certainly, what exactly willinterest you in the Internet first of all — people or computers, — depends onlyon 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 speechgoes about millions computers and their users all over the world, connected ina uniform network, the metaphor this already ceases be simply metaphor. That iswhy by exaggeration will not tell, that, leave in the Internet, you do (make)for yourselves accessible the whole world.

1. Basic protocols inInternet and search in them.

Internet contains vastquantity (amount) of the information, on this in it(him) it is difficult tofind that that is necessary if not to know where to search. The place of apresence(finding) (or address) each resource defines(determines) it(him) URL.In URL the type of the protocol indicating on what server contains the accessis carried out: on WWW (on which specifies recording: http), Gopher, ftp,telnet, or WAIS, it depends on that what type of the information you willtransfer. The network protocol — set of the precisely certain rules: how torequest, to make out and to send on a network the given version of theinformation


Millions computers arejoined(attached) to a network Internet and many from them have interestingopportunities.

It appears, is quite feasibleto reach these computers to look databases, available in them, and programs.The special program telnet allows to transform your computer into the clienttelnet for a data access and programs in numerous servers telnet. For exampleresearcher regularly can work on several computers, which managers nominate toit(him) a special name and password.

In itself telnet — thecommunication facility is simple; neither any of the own interface, noropportunities of search it(he) does not give.

Having contacted the helptelnet with the removed machine and having entered in a field of search theentrance name (login) and password (password) you communicate with this machineand programs on further to it(her), and telnet cares only of maintenance ofcommunication(connection) between you.

Certainly, many storehousesof the information, which were originally served by the special programs withaccess on telnet now it is possible to transfer(translate) on WWW, that notseldom and is done(made). However there were also such which on former give theservices only on telnet (especially among the catalogues and informationservices of libraries).

Standard the link on telnetconnection with some site Internet (i.e. URL- the address of this connection)looks so:

telnet: // < the addressof the server >


Practically information isstored(kept) in the computer world as files. On this for itself зареInternet thespecial means for an exchange of files on a network — network protocol FTP(File Transfer Protocol) has appeared.

The quantity(amount) offiles accessible on sites of all world on anonymous FTP is measured inastronomical figures and constantly grows. Besides Word Wide Web allows withoutany alteration existing FTP of archives, to supply with their descriptions ofany degree of detail and convenient hypertext interface.

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


The search on a name of afile on all anonymous FTP-sites of the world can be carried out with the helpof system Archie. She(it) is developed by the several programmers fromuniversity Magellan in Canada and carries out indexation of stations FTP,showing files, accessible in everyone station. Archie informs several millionsfiles taking place in more thousand stations FTP, and gives a surprisingly fastway of search of that place, where it is necessary to be directed for receptionof a file, interesting for you. The search in a database of the server Archieis made with the help of keywords, which in this case represent simply names offiles or fragments of names.

Now Archie is accessiblethrough WWW. It WWW page with the form in which the keywords and options ofsearch are specified.

Though the name of a filealmost always has a certain attitude(relation) to his(its) contents, to useArchie for thematic search of the programs does not cost. This system will beuseful, if you really know a name of the necessary file or part of a name. Onthe other hand if you search for the program, which has the standard reducedname, that is some probability that this reduction will be present and at aname of a file, so it is possible to try to find such file with the helpArchie. The results of search represent the list of FTP-sites and completenames 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 willtransfer you to the initial catalogue of file system on this archive.

Archie the list into thelist into the list into the list into the reception.

URL-address indicatingFTP-connection, owes, as a minimum to include a word “ftp” as the left part andaddress of the site in right:

ftp: // < the address ofthe server >.


 Almost all information resources Internet givean 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 representsthe huge distributed(allocated) database, i.e. the separate parts of thisdatabase are located on different net points worldwide. The program — clientfor work with servers WAIS not only is able to communicate with them under thespecial protocol, but also stores(keeps) the list of all databases WAIS withtheir addresses and names, and sometimes and with the brief descriptions. Thereit is possible to find archives of news, every possible catalogues,directories, collections of scientific clauses and abstracts, indexes and muchanother. Practically any information, for which the database is the convenientform by performances which is interesting enough to a wide audience, can besubmitted in WAIS.

The database WAIS is sogreat, that idle time of recordings — extremely unpromising way of access tothe information. Therefore in WAIS the rather complex(difficult) method ofkeyword search and phrases is applied. The documents received as a result ofsearch, are sorted by the WAIS-server by quantity(amount) of entry in them ofkeywords and on, as far as is complete in each of them all set of the orderedkeywords is submitted. Such system is capable to give good results, is especialif to break process of search at some stages.

The first stage of searchusually 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 thosekeywords, which at the end interest you, and those general(common) conceptsconcerning your field of knowledge.

Having chosen on the firststage of one or several bases, it is possible to begin search actually ofdocuments — that also it is possible to do(make) in some calls, gettingacquainted after each search with results and changing the list of keywords,the necessary document will not be found yet. Besides WAIS has one usefulproperty: if at the next stage of search you have found the document, whichcontents are especially close that you search, it(he) can be added to the listof the relevant documents. In result at the following stage WAIS will find thedocuments, not only containing a set of your keywords, but also similar on thedictionary structure on those texts, which you have specified as most suitable.

Though Netscape is capableto work with servers WAIS, for this purpose it(he) should know the address ofthe special proxy for the protocol WAIS, of which your provider can not appear.The special WAIS-clients working including under Windows, not only convenientfor interactive search in databases, but also allows to manage services any ofthe server – intermediary.

URL-address for WAIS looksas:

wais: // < the address ofthe server > /


Each of the considered tillnow Internet protocols quite could exist in itself: telnet gives access to theprograms, FTP — to files, WAIS — to databases. All these systems were createdboth developed almost independently from each other and put before itself theconcrete purpose — to construct the mechanism of access to one certain kind ofresources.

However as Internet of dewsalso became complicated, it(he) pushed the people to an idea, that theinformation on a nature is uniform and what not too reasonably to divideher(it) on different “ kinds of resources ” with unlike methods of access. Bythe end of 80-s' years the idea of a new universal remedy of work with thediverse information was carried in air.

The first system called toembody for life these dreams began Gopher, appeared on light 1991 at theAmerican university of state Minnesota. Fundamental concept incorporated inits(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 passingfurther from one submenu in another, it is possible to engage actually insearch of the information. The information in system Gopher is organizedstrictly hierarchically, “from the general to the particular”. On each step theserver sends yours Gopher — client not only contents of the next menu, but alsoservice information on, where there are objects appropriate to items it themenu. The client deduces on the screen only transfer of items, but when youchoose one from them, it(he), having verified with the information, availableat him(it), or will send on any of Gopher — servers search about distributionof the following of the menu, or will try to establish FTP- or telnet-connection with some site Internet.

Obviously from allinformation tools Internet Gopher most of all is similar on WWW — both thesesystems are called to serve the shell with diverse resources. However Gopher isdeprived of those rich representational means, which do(make) WWW not onlyinformation 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 simplifiesintegration itself Gopher as one of kinds of resources in WWW. Practically allthat is told about work with Gopher — by the client fairly and for travel onsystem Gopher with the help of a browser WWW.

URL of one the menu consistsof items Gopher — from addresses Gopher- of the server and listed those itemsof the menu, which will result you in initial item:

gopher: // < the addressof the server > /  


In spite of the fact thatper the first years of the existence Gopher has won the large popularity, theneed in any became ripe more simple and in too time to maximum universalsystem, in which communication(connection) between resources would be more freeand 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, isexacter than hypermedia. The hypertext is a text of which component areconnected with each other and to other texts with the help of the links. Thehypermedia is that that will turn out from a hypertext if to replace inhis(its) definition a word “text” on “ any kinds of the information ”: thegraphic images, video, sound etc.

World Wide Web “world wideweb” means literally. Why she(it) so refers to as. As it is clear from thename, she(it) is global. You not always know in what part of light there is acomputer, 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 buttonof the mouse. WWW is similar to a web. It is a complex(difficult) informationnetwork connected hypermedia by communications(connections). WWW allows to notrefuse information resources already saved in Internet, other means, accessiblewith the help, — FTP, telnet and Gopher. It is more than that, the work withthese resources through WWW is so convenient, that, say, FTP-clients, former atone time by separate class of the programs, now are used only by few.

And nevertheless main inWorld 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 WWWhardly in general when or would get in a network. Speed of creation andupdating, the rich representational opportunities in a combination to ease ofaccess and huge audience have made WWW by new mass media. The start WWW-serversand creation of WWW-pages already has turned of a style to new business — withall that is peculiar to modern business: by a payment for square centimeters ofthe advertising area.

On the other hand, the fastdistribution of system so naturally uniting diverse resources, was promoted notin the last instance by its(her) origin not in недрахof a businessconcern, and in scientific establishment — European laboratory of physics ofparticles, which employees did not begin to do(make) of secrets of thedevelopment and have not tried at all on it(her) to grow rich.

Fortunately, nature WWW asfirst of all means of search and organization of the information allows tohope, that this remarkable invention to not turn to the tool of only onecommerce and advertising.

The servers and clients WWWcommunicate among themselves under the special protocol HTTP (Hyper TransferProtocol, hypertext transfer protocol). URL for WWW looks as:

http: // < the address ofthe server >

To pass from one page Web toanother — an interesting way of research World Wide Web, however you early orlate need to find something concrete. But thus it to make it will be notpossible. In Internet there are special tools of Web-search.

Tools of search in WWW.

 Tools of search of the information inInternet, constructed on different principles and pursuing the different purpose,exists much. But all unites them that they settle down on the speciallyallocated network computers with powerful channels ofcommunication(connection), serve every minute huge quantity(amount) of thevisitors and require(demand) of the owners of significant expenses on supportand updating. Nevertheless, almost all of them respond on searches of the userscompletely бескорыстно, and the sponsors and advertisers pay for thispleasure. On scales of influence on network community of retrieval systems,undoubtedly, are one of corner stones Internet.

The classification ofretrieval systems is more convenient for building all on the basis of on thetax and processing of the information given to the users, — or else how many isautomated in them, who types(collects) a database, in which the search is made:the people or computers.

2. Tools of search

Conditionally tools ofsearch are subdivided into search means of a help type (directories) andretrieval systems in the pure state (search engines).

2.1 Thematic catalogues

The search tools of thefirst type name subject, or thematic catalogues more often. The company owningsuch catalogue, continuously conducts huge work, investigating, describing,cataloguing and displaying on half-glasses contents of WWW-servers and othernetwork resources scattered worldwide. Result her(it) titanium of efforts isthe constantly updated hierarchical catalogue, at the top level the mostgeneral(common) categories, such as “business” are assembled,"”science", "”art" etc., and the elements of the lowermostlevel represent the links to separate WWW-pages and server together with thebrief description of their contents.

Guarantees that suchcatalogue really covers all contents WWW, nobody will give, howeverpossible(probable) not the completeness and selection of materials is withinterest expiated there, that for the present not under force to any computer — intelligence of selection.

The subject catalogues givealso opportunity of keyword search. However search this occurs not in contentsof WWW-servers, and in their brief descriptions stored(kept) in the catalogue.

The subject cataloguesInternet can be counted literally on fingers, as their creation and supportrequire(demand) huge expenses. To most known concern Yahoo, WWW VirtualLibrary, Galaxy and some other.


Is most popular in thepopulation Internet the catalogue Yahoo. On the first page Yahoo, located tothe address www.yahoo.com, you receive access to two basic method ofwork with the catalogue — keyword search and hierarchical tree of sections.

Having begundescent(release) on sections of the catalogue, you will see, that each sectioncontains the precisely same field for input of keywords and button Search,starting search.

Each section can include astransfer included in him(it) and actually links to pages concerning at once allsection, with their brief descriptions.

Instead of travel you can atonce 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 ofsearch and having pressed the button Search, you receive the list all in Yahoo,that comprises the specified keywords. This list will be divided(shared) intotwo parts — “categories” and “sites”.

If total of the linksreturned as a result of search, exceeds 25, the list of the links will bebroken on some parts.


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 becomestricter selection of the information brought in the catalogue. One of mostknown such systems — catalogue Magellan to the address: http: //www.mckinley.com

This database contains theitems of information on 80 thousand WWW-pages — that very much not much incomparison with those in millions, which exist in a network. However if Yahooas the description of a resource uses one — two lines of the text, theemployees of system Magellan on some of pages brought in their database, writethe small reviews, and also estimate quality of these information resources ona five-mark scale. Till past bases of the reviews, Magellan owns as an ownautomatic index, for search in which it is necessary to throw the switch undera field of input in a rule(situation) entire database.

As a rule search representsone or several keywords divided(shared) by blanks.


The service, similar by theprinciples, of firm Point (http: // www.pointcom.com) in general basic emphasisdoes(makes) not on search, and on work with the thematic catalogue.

The service Point is knownin a network for that its(her) employees are constantly engaged оцениваниемof networkresources and conduct the lists of those sites, which they consider(count)belong to “ to the best five percents(interests) WWW ”.

Firm Point Conducts a shareddatabase all “ of five-percentage WWW-pages, where about everyone it ispossible to read the detailed license.

Virtual Library.

The most old subjectcatalogue WWW is the catalogue Virtual Library:

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

This system full enoughcovers a scientific layer WWW — servers of universities, laboratories andeducational institutions.

Russia-On-Line SubjectGuide.

For the users in our countrythe certain interest can represent the thematic catalogue Russia-On-LineSubject Guide, located to the address www.online.ru/rmain. Thiscatalogue contains rather motley assembly of the links on foreign sources plusthe thematic review of the Russian and Russian resources WWW.

2.2. Automatic indexes.

It is possible to approachto 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 beginsautomatically to download from a network the documents on it URL, and from eachnew document she(it) takes all links, contained in it,(him,) and adds them inthe base of addresses. As at the end all WWW the documents are connected amongthemselves, early or late such program will bypass all Internet.

Certainly, the program cannot understand as or classify that she(it) sees in a network. The programs ofsuch type refer to as robots. They are limited to the tax of the statisticalinformation and construction indexes in the texts of the documents. Thedatabase, collected by the robot, — index — stores (keeps) in it, simplyspeaking, item of information on that in what WWW-documents to contain those orother words.

Such the automaticallycollected index also underlies retrieval systems of the second sort, whichfrequently and name — automatic indexes.

The automatic index consistsof three parts: the program — robot collected by this robot of a database andthe interface for search in this base, with which the user works. All thesecomponents quite can function without intervention of the man.

As any classification ofmaterials in such systems are absent, it is necessary to resort to them onlythen, when you precisely know keywords concerning that it is necessary, — weshall tell, a surname of the man or it is enough some of rare terms from theappropriate area. If to set search on the a little widespread words, you willhave not enough life to bypass all URL-addresses, received as a result ofsearch, — for example, the index of system Alta Vista contains of 11 billionswords taken from 30 millions of WWW-pages.

An automatic index ofWWW-pages exists much: WebCrawler, Lycos, Excite, Inktomi, Open Text andothers. Some of them (for example, Lycos) represent more or less successfulsynthesis of the subject catalogue and automatic index.

Alta Vista.

Its(her) addresshttp://altavista.digital.com. This system has appeared in December 1995. She(it) one of largest on volume of indexes from all such retrieval systems bothmost powerful and floppy rules of construction of searches. Alta Vistaunderstands two different languages of searches rather strongly distinguishedfrom each other. On the first page Alta Vista you see the form for simplesearch (Simple Search), and the panel of heading at the top of page containsthe button Advanced Search, having pressed which, you receive the form forcomplication of search.

Except for WWW-pages, AltaVista conducts a separate index for clauses from more than 14000 conferencesUsenet (including hierarchy of groups relcom. *).

Search Alta Vista: that AltaVista worked on group of words, only when they cost(stand) beside, it isnecessary to conclude this group in inverted commas. If it is necessary toexclude from result all documents containing a certain word, it is necessary toattribute this word with is familiar “minus”.

The word without any markworks in search precisely the same as also it with is familiar “plus”.

As against Yahoo, by defaultAlta Vista searches of entry of the whole words. The ordered terms should standin 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 intostructure of other words, use a symbol *. The asterisk can stand only at theend of a word, and prevent giving many (too much) of results, Alta Vistarequires(demands), that the word which is coming to an end on *, should consistnot less than of 3 letters. Moreover, a symbol * allows to find not anytermination (ending) of a word, but only not exceeding length of five symbolsand not containing of capital letters or figures.

Results of search AltaVista, 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 youwill see simply first some lines of his(its) text. If will be found more than10 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 “mostimportant” documents with your keywords at definition of a degree of importancetaking into account the following factors:

 Whether the keywords into heading of thedocuments enter;

 Whether these words in the first several linesof the documents contain;

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

Info seek

Info seek, entered in ofoperation at the end of 19996 years, is somewhat reminiscent Alta Vista,however volume of the complete texts, surveyed by him,(it,) of the documentsyet does not exceed 30 million. Web-pages. The address:www.infoseek.com. It is rather powerful system having high speed andidle time in circulation. Opportunities of drawing up of search almost same, aswell as in Alta Vista, but not so rich. At almost complete preservation ofvalues of marks "«plus", "«minus" and "«invertedcommas", sensitivity to a difference header both lower case letters andopportunity to limit search to fragments Web- of pages, Info seek yet has noability to define(determine) beside the worth terms (there is no operatorNEAR), to limit search by date of updating a source and, main, to truncateterminations(ending) the key terms.

But the given retrievalsystem contains weight of facultative functions., for example, opportunityconcerns to those to define(determine) quantity(amount) of the links in WWW onconcrete page, that is to judge, as far as she(it) is popular or, on thecontrary, to find out, how many links to external pages contain on the givensite, more correctly, how many from them are reflected in index files Ultraseek. Use of special function Image seek allows to find in Internet of theimage (figures, photo) on the certain subject. Info seek has also one of thebest directories of resources of a Network.


By one of powerful searchmeans in World Wide Web can attribute (relate) HotBot, containing the items ofinformation on the complete texts 110 million. Pages. The address: www.hotbot.com.HotBot belongs to the newest systems, therefore his (its) profound search givesamazingly ample opportunities for detailed elaboration of search. It is reached(achieved) at the expense of use of the multistage menu offering various variantsof drawing up of the search instruction. It is possible to carry out search onpresence in the document one or several terms, search on a separate phase,search of the concrete person or links to the certain electronic address. Forthe greater detailed elaboration of search probably application of conditionsSHOULD (can contain), MUST (should necessarily contain), MUST NOT (should notcontain) in relation to any concepts. Besides HotBot represents возможностьограничитьsearch by dateof creation or last updating of the document, on geographic a rule(situation)of the server. Top of service opportunities is the search of the documentscontaining certain types of files, for example video. For this purpose it isnecessary only to make a mark in special item of the menu of search.


It is one more tool ofsearch such as search-bot (search          the robot). The address: http: //www.webcrawler.com. The search here is very simple. Enter maximal keywords intoa field of search, press Search.


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

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


World Wide Web Worm.


You will find this tool ofsearch on www.cs.colorado.edu/home/mcbryan/wwww.html. It is one moreextensive index of sites Web.

In each concrete case it isexpedient to use the tool of search. You should try to carry out(spend) searchthrough one tool and, if you have not received results, to pass to another. Butnevertheless what tool to use? First of all it is better to take advantage ofthe thematic catalogue such as Yahoo, size at them rather small, but the speedis great. If to find the necessary information it was not possible, it speaksthat you are interested in a too narrow subject, or badly correspond with yoursubject the keywords, chosen by you. It does not mean, that the necessaryinformation in WWW is not present — it will be simple to find her(it) moredifficultly. For its(her) search to you will be reached to take advantage ofmore primitive, more automatic and consequently by more universal systems suchas Alta Vista.

2.3. Russian retrievalsystems

The retrieval systems ofglobal scale concentrate the basic attention on English resources of a Network.The task of search of the information on servers within the limits of theseparate countries is carried out with systems of local character speciallyadapted for features of concrete languages. There are similar search means andin Russia. All of them are united by (with) an opportunity of processing ofmaterials in all Cyrillic codes*. However on capacity and level of offeredservice the Russian retrieval systems considerably differ from each other.

 Rambler, "Апорт" and "Яndex" nowconcern to leading group systems.


Among favorites is allocatedRambler (http://www.rambler.ru), becoming with the first professional domesticretrieval system. This system provides full text search on 3 million. Pageslocated on more than 15 thousand Web sites of Russia and the countries of nearforeign countries. Besides Web-servers, the week archive of news of hierarchyrelcom is surveyed also.

Rambler has close to anoptimum conclusion of results of search. Even in a normal form the link onfound object  inserts the complete information.The system is designed in such a manner that the same document in the variouscoding 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 analyzeof the received results because of absence of duplication of the samedocuments.

The main lack Ramblerconsists in impossibility to carry out search on the whole phase or even tospecify in searches limiting distance of the required terms from each other.The casual combination of completely untied words results in distribution ofthe links on the documents, are absolutely not relevant to search.


The retrieval system Апорт(http://www.апорт.ru) is suppliedwith weight of various functions carrying her(it) number user-friendliest.

One consists of the mainadvantages Апортin ample opportunities of drawing up of search.Besides the traditional operators «both» and “or”, search on thewhole phase, the system is capable to isolate combinations of the terms locatedin the text by a number (line) with each other. Апортoffers anopportunity of machine translation of search with Russian on the Englishlanguage and on the contrary. Both Rambler, and Апортare capable toallocate the same document in the various coding and to give out the link tohim (it) only of time, listing(transferring) concrete addresses in the listURL. Unfortunately, thus the items of information on the out-of-date versionsof the same page in time do not leave which are listed (transferred) asexisting, having a difference only in date of updating. One more lack of thissystem is not always correct processing of the names of pages, because of whatas a result of search the document without the name » frequently is underlined«.


Retrieval system Яndex(http://www.yandex.ru), where besides servers of domains «ru< and «su< Яndex индексируетthe contents offoreign Russian Web-sites.

The main distinctive featureof this system is the deep morphological analysis of the process able terms.The most powerful linguistics allows to take into account practically allpossible (probable) shades of the use of keywords and to make search maximumprecisely. Яndex has the good mechanism of recognition of onedocument in the several coding or on mirror servers.

After leading Russian тройкойthere are somemore 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 donot differ neither breadth of search, nor by comfort, and can be used only asaddition to conducting search means.

The search service in theRussian block Internet, as well as all over the world, develops promptly. Thereis no doubt, that in the near future parameters of existing systems will beraised, the new generations of search means giving to the users still (even)the large opportunities will appear.

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