The concept of specialized search engines. Link exchanges necessarily entail sanctions. Guaranteed growth in contacts and number of customers

SEARCH FOR INFORMATION ON THE INTERNET

Internet Information Search Tools

Current growth information resources   The internet is going fast. The World Wide Web resembles the library’s reading room, which stores gigantic volumes of text, graphics, multimedia, archive and other files. This hall cannot be completely circumvented. Here everything changes hourly, the number of various documents increases every second. Finding the right information is becoming increasingly difficult. Various printed guides become obsolete even before they are published. The only reliable way to search for information is to use special search enginesthat constantly monitor changes in information on the network.

Search engines   - this is special softwarewhose main task is to organize the most optimal search for information on the Internet.

The search engines known today are divided into the following main groups:

Search engines general purpose   (automatic indexes);

Subject directories (directories) of the Internet;

Specialized search engines;

Metasearch systems.

General Purpose Search Engines

Creating a universal search service, which allows finding information from various Internet resources, became possible only with the advent of the World Wide Web servers in the beginning of the 90s. Along with the advent of the World Wide Web servers, special search engines, whose main function is to search for information among various Internet information resources, including World Wide Web, FTP, Gopher, Usenet newsgroups servers, email Address Lists.

The strategy of modern search engines is based on two approaches. In the first case, huge databases are created and continuously updated that store information about the millions of documents available on the Internet. Information is automatically collected by special programs (called robots, spiders, etc.) that scan Internet servers, copy documents, analyze the words that are encountered, and perform indexing.

Indexing is choosing all meaningful wordscalled key. Some search engines process the entire document, while others only separate parts of the document: names, headings, initial words of sections. The document indexes thus generated — the keyword databases — are added to existing ones and stored on search engines. Usually this process does not require any effort on the part of the person, since these tools completely hide from the user the way of organizing the database and its contents. Search engines of this kind are most often called general purpose search enginesor automatic indexes.An automatic index consists of three parts:

Robot programs;

Databases collected by this robot;

The interface for searching the database.

Typical representatives of automatic indexes are, for example, AltaVista   andLycos. From the user's point of view, automatic indexes work quite simply: the user sets a keyword or phrase constructed from keywords according to certain rules, and the search engine in response to a query returns lists and exact addresses (URLs) of those documents that correspond to this query.

Thematic catalogs

Another approach involves the organization of a search server as a subject-oriented system, where information on individual topics is collected in the corresponding directories. Examples are servers Yahoo   andGalaxy. Search engines of this kind are often called subjector thematic catalogs.Thematic catalogs are used in cases where it is difficult to formulate a query using keywords due to the specifics of the information sought or lack of knowledge on a topic of interest.

Information is entered into the catalog at the initiative of a person. The page to be added must be strictly linked to the categories accepted in the catalog. The result is a constantly updated tree-like catalog, at the top level of which the most general categories are collected, such as “business”, “science”, “education”, etc., and the elements of the lowest level are links to individual Web pages and Web sites along with a brief description of their contents.

By selecting the desired section, the user receives a list of subsections, a narrowing circle, and so on until he gets to a page containing links to necessary information. Subject directories cannot compete with search engines by the breadth of information coverage. Their advantage is that the probability of accessing information that is not related to the topic of search is very small. To facilitate viewing of information resources, many subject catalogs have their own simple search engines that allow searching through keywords   inside the directory itself. Only the search is carried out not in the contents of the Web servers themselves around the world, but in their brief descriptions stored in the catalog database. Note that the oldest Yahoo directory is a hierarchically organized Web directory that is generated semi-automatically. Links to various resources are collected in two ways: they are sent by users and retrieved by robot programs.

Specialized Search Engines

At that time, when the World Wide Web servers did not exist on the Internet, information search on the global network was already available using several network search engines, each of which searched only in its own area: search in Usenet archives, search for addresses email   etc. Such systems are still in use and are called specialized search engines. For example, to find files by their names on FTP servers, the Archie system is used. Veronica performs a similar function among the servers served by the Gopher system.

Specialized search engines use a fairly simple search technology. Their main advantage lies in the high degree of compliance of the information found with the user's requests. However, such specialized directories and indexes of the system are slower than the popular general-purpose search engines.

Metasearch systems

If the same query is sent to different search tools, the search result will be different both in the number of documents found and in their compliance with the search query. Meta-search systems, or meta-indexes, allow you to improve your search by sending a query to several search engines at the same time. The documents obtained as a result of the search are combined into a common list ordered in a certain way.

Meta-search saves time, since there is no need to poll each search engine separately, and increases the likelihood of obtaining the information that the user needs. The disadvantage of meta-search is that when accessing different search engines, the query has to be formulated in a form that is understandable to all machines. This does not allow the use of subtle individual settings and capabilities of each individual machine.

Questions

1. What types of search engines are used to search for information on the Internet?

2. Describe how automatic indexes work.

3. What are metasearch engines?

4. What are the advantages and disadvantages of metasearch engines?

5. What are specialized search engines used for?

Internet Information Search Technology

First steps to find necessary information   determined by the extent to which the user owns the topic under study. If there is only a general idea of \u200b\u200bthe topic, then it is natural to start the search with subject catalogs. There are no special problems. The user will surely find links to information databases or individual documents.

In cases where the user speaks the terminology and searches for original, specific documents, it is more convenient to search using general-purpose search engines.

General Search Engine Requirements

From the point of view of the user, communication with search engines should be simple, not requiring training and special skills. The user must be able to.

1. Make a request in your native language in a natural way. For example, “Using computers to conduct history lessons in high school.”

2. Limit the search area of \u200b\u200bdocuments. This restriction can be determined by the place and time of creation of the document, the language in which it is written, the subject of the information sought. 3. In response to a request, get a list of documents found with a brief description. Documents should be as relevant as possible.

4. If necessary, download the necessary documents to your computer for future use.

Actions search enginehidden from the user should be as follows.

1. Translation of keywords into a given language.

2. Selection of synonyms for keywords.

3. Consideration of morphological variants of words. For example, look for documents containing not only the word “car”, but also “cars”, “cars”, etc.

4. Searching in the languages \u200b\u200bindicated by the user.

5. The semantic selection of documents found according to their subject matter of the request.

6. Systematization of documents according to the degree of their compliance with the request.

7. Presentation of the documents found in a convenient and understandable for the user form.

Each of the search engines offers two search methods - plainand complicated.

Simple searchconsists in the fact that the query consists of a set of keywords, and the search engine returns documents containing at least one of these words. It is clear that with such a search a lot of extra documents will be found that are not of interest to the user.

To increase the efficiency of the search, it is necessary to use developed search tools that allow you to formulate accurate complexinquiries. Rules for building complex queries can be found in the help files of each search engine.

Search all forms of the word

To search for all words with a common root, use the * sign. For example, as a result of a search on request a computer*documents containing the words will be found: computer, computers, computer, computeretc. A number of search engines do this automatically, looking for documents containing all the morphological forms of the keyword.

Phrase search

Double quotes are used to search for a phrase or phrase in a document. Upon request "Information technology"documents containing this phrase with no options will be found.

Keyword inclusion and exclusion

The plus sign indicated before the word or phrase without a space requires the inclusion of this word (phrase) in the document, and the minus sign requires its exclusion. This means that for the search “Internet Search” - “search engines”, documents containing the phrase “search engines” will be excluded from the list of documents found for the search “Internet Search”.

Logical queries

In such queries, the logical operators OR, AND, NOT, and NEAR are used, combining several words or phrases into one query.

OR   (or)

When query elements are connected by the OR operator, this means that at least one of them must be present in any of the documents found. Example: detectiveOR detective.Upon this request, documents containing both words and each of them individually will be found.

AND   (and)

This logical operator is used when the presence of all the words connected by it is necessary. Example: informationalAND technologies.The documents found will contain both words. But this does not mean that they are close to each other in the text or are related in meaning.

NOT   (not)

Words or phrases before this operator will be excluded from the search results. Example: "search on the Internet"NOT "Search engines".Such a request is similar to + "Search on the Internet" - "search engines."

The operator indicates that two words should be separated by no more than ten words. In a number of search engines, curly brackets and square brackets are used to request a search for words located at a certain distance.

Display Search Results

Each search engine presents search results differently to users. This is usually a numbered list of documents found upon request. For each document, as a rule, its name, URL, size, time of updating the document and the first few phrases of the text, by which you can judge its contents, are reported. A number of search engines provide a brief summary from which you can get an idea of \u200b\u200bthe context in which keywords are used.

The name of the document and its URL are issued in the form of a hyperlink, through which the user has the opportunity to download the document to his computer for reading, saving and printing. The search system evaluates the search results and displays a list of documents in a specific order (ranking documents). Thus, at the top of the list there will be documents with a higher degree of compliance with the request.

Each search system uses its own criteria for ranking documents both in the analysis of search results and in the formation of the index. As a result, the search result for the same query will be different for each search tool.

The user can affect the ranking of documents by specifying in the appropriate window the most meaningful words   and phrases. In this case, the ranking will be carried out in such a way that at the top of the list are documents containing these words and phrases.

Questions

1. In what cases is it advisable to use thematic catalogs to search for information on the Internet?

2. What search options should a user provide for a general search engine?

3. Make a search for documents containing the word fruitand one of the words freshor exotic.

A search system is a hardware and software system designed to search the Internet and respond to a user’s request, specified as a text phrase (search query), by issuing a list of links to information sources, in order of relevance (in accordance with the request). The largest international search engines: Google, Yahoo, "MSN". On the Russian Internet it is - Yandex, Rambler, Aport.

We describe the main characteristics of search engines:

Completeness

Completeness is one of the main characteristics of the search system, which is the ratio of the number of documents found by request to the total number of documents on the Internet that satisfy this request. For example, if on the Internet there are 100 pages containing the phrase “how to choose a car”, and only 60 of them were found by the relevant query, then the search will be 0.6. Obviously, the more complete the search, the less likely it is that the user will not find the document he needs, provided that he even exists on the Internet.

Accuracy

Accuracy is another main characteristic of a search engine, which is determined by the degree to which the documents found match the user's request. For example, if the query “how to choose a car” contains 100 documents, 50 of them contain the phrase “how to choose a car”, and the rest just have these words (“how to choose the right radio and install in a car”), then the search accuracy is considered equal to 50/100 (\u003d 0.5). The more accurate the search, the faster the user will find the documents he needs, the less various kinds of “garbage” among them there will be, the less often the documents found will not match the query.

Relevance

Relevance is an equally important component of the search, which is characterized by the time elapsing from the publication of documents on the Internet until they are entered in the index database of the search system. For example, the day after the appearance of interesting news, a large number of users turned to search engines with relevant requests. Objectively, less than a day has passed since the publication of news on this topic, however, the main documents have already been indexed and available for search, thanks to the existence of the so-called “quick database” in large search engines, which is updated several times a day.

Search speed

Search speed is closely related to its resistance to stress. For example, according to the data of Rambler Internet Holding LLC, today in working hours about 60 queries per second arrive to the search engine Rambler. Such congestion requires reducing the processing time of a single request. Here, the interests of the user and the search system coincide: the visitor wants to get the results as quickly as possible, and the search engine should fulfill the request as quickly as possible so as not to slow down the calculation of the following queries.

Visibility

Visual presentation of the results is an important component of a convenient search. For most queries, the search engine finds hundreds, or even thousands of documents. Due to the vagueness of the compilation of requests or inaccuracy of the search, even the first pages of the issue do not always contain only the necessary information. This means that the user often has to do his own search inside the list found. Various elements of the search engine results page help navigate the search results. Detailed explanations on the search results page, for example, at Yandex, can be found here http://help.yandex.ru/search/?id\u003d481937.

4. A brief history of the development of search engines

In the initial period of development of the Internet, the number of its users was small, and the amount of information available was relatively small. For the most part, only research workers had access to the Internet. At this time, the task of finding information on the Internet was not as relevant as it is now.

One of the first ways to organize access to network information resources was the creation of open site directories, links to resources in which were grouped according to the subject. The first such project was Yahoo.com, which opened in the spring of 1994. After the number of sites in the Yahoo directory increased significantly, the ability to search for the necessary information in the directory was added. In the full sense, this was not yet a search engine, since the search area was limited only by the resources present in the catalog, and not by all Internet resources.

Link directories have been widely used before, but have almost completely lost their popularity today. Since even modern catalogs, huge in their volume, contain information only about a negligible part of the Internet. The largest directory of the DMOZ network (also called the Open Directory Project) contains information on 5 million resources, while the Google search engine database consists of more than 8 billion documents.

The first full-fledged search engine was WebCrawler, published in 1994.

In 1995, the search engines Lycos and AltaVista appeared. Last many years has been a leader in the field of information search on the Internet.

In 1997, Sergey Brin and Larry Page created a Google search engine as part of a research project at Stanford University. AT this moment   Google is the most popular search engine in the world!

In September 1997, the Yandex search engine, which is the most popular on the Russian-language Internet, was officially announced.

Currently, there are three main international search engines - Google, Yahoo and MSN, which have their own databases and search algorithms. Most other search engines (of which there are a large number) use in one form or another the results of the three listed. For example, AOL search (search.aol.com) uses the Google database, and AltaVista, Lycos, and AllTheWeb use the Yahoo database.

5. The composition and principles of the search engine

In Russia, the main search engine is Yandex, followed by Rambler.ru, Google.ru, Aport.ru, Mail.ru. Moreover, at the moment, Mail.ru uses the Yandex search engine and database.

Almost all major search engines have their own structure, different from others. However, it is possible to identify the main components common to all search engines. Differences in structure can only be in the form of the implementation of the mechanisms of interaction of these components.

Indexing module

The indexing module consists of three auxiliary programs (robots):

Spider (spider) - a program designed to download web pages. "Spider" provides the download page and extracts all internal links from this page. The html code of each page is downloaded. Robots use HTTP protocols to download pages. The "spider" works as follows. The robot sends a “get / path / document” request and some other HTTP request commands to the server. In response, the robot receives a text stream containing service information and the document itself.

Page URL

the date the page was downloaded

server response http header

page body (html code)

Crawler ("traveling" spider) is a program that automatically follows all the links found on the page. Selects all links present on the page. Its task is to determine where the spider should go next, based on links or based on a predefined list of addresses. Crawler, following the links found, searches for new documents that are still unknown to the search engine.

Indexer (robot indexer) is a program that analyzes web pages downloaded by spiders. The indexer parses the page into its constituent parts and analyzes them using its own lexical and morphological algorithms. Various page elements are analyzed, such as text, headings, links, structural and style features, special service html tags, etc.

Thus, the indexing module allows you to crawl a given set of resources by links, download pages that appear, extract links to new pages from received documents, and perform a complete analysis of these documents.

Database

A database, or a search engine index, is a data storage system, an information array in which specially converted parameters of all documents downloaded and processed by the indexing module are stored.

Search server

The search server is an essential element of the whole system, since the quality and speed of the search directly depend on the algorithms that underlie its functioning.

The search server works as follows:

The request received from the user is subjected to morphological analysis. The information environment of each document contained in the database is generated (which will subsequently be displayed as a snippet, that is, the corresponding request textual information   on the search results page).

The received data is transmitted as input parameters to a special ranking module. Data is processed for all documents, as a result of which, for each document, its own rating is calculated that characterizes the relevance of the request entered by the user and the various components of this document stored in the search engine index.

Depending on the user's choice, this rating may be adjusted by additional conditions (for example, the so-called “advanced search”).

Next, a snippet is generated, that is, for each document found, a heading, a brief annotation that most closely matches the query and a link to the document itself are retrieved from the document table, and the words found are highlighted.

The obtained search results are transmitted to the user in the form of SERP (Search Engine Result Page) - the page for issuing search results.

As you can see, all these components are closely related to each other and work in collaboration, forming a clear, quite complex search engine mechanism, which requires huge resources.

No search engine covers all Internet resources.

Each search engine collects information about Internet resources, using its own unique methods, and forms its own periodically updated database. Access to this database is provided to the user.

Search engines implement two ways to search for a resource:

Search by subject catalogs - informationis presented in the form of a hierarchical structure. At the top level - general categories ("Internet", "Business", "Art", "Education", etc.), at the next level, the categories are divided into sections, etc. The lowest level is links to specific web pages or other information resources.

Search by keywords (index search or detailed) - the user sends to the search engine requestconsisting of keywords. System returnsthe user a list of resources found by request.

Most search engines combine both search methods.

Search engines can be local, global, regional, and specialized.

In the Russian part of the Internet (Runet), the most popular search engines are Rambler (www.rambler.ru), Yandex (www.yandex.ru), Aport (www.aport.ru), Google (www.google.ru).

Most Search Enginesimplemented as portals.

Portal (from Englishportal - main entrance, gates) is a website that integrates various Internet services: search tools, mail, news, dictionaries, etc.

Portals can be specialized (such as,www. museum. ru) and general (e.g.www. km. ru).

Keyword Search

The set of keywords that are being searched is also called the search criteria or search topic.

A request can consist of either a single word or a combination of words combined by operators - symbols by which the system determines what action it needs to perform. For example: the query “Moscow Peter” contains the operator AND (a space is perceived), which indicates that you need to look for documents that contain both words - Moscow and Peter.

In order for the search to be relevant (from the English relevant - relevant, relevant), several general rules should be taken into account:

Regardless of the form in which the word is used in the query, the search takes into account all its word forms according to the rules of the Russian language. For example, by the query “ticket” the words “ticket”, “ticket”, etc. will be found.

Capital letters should be used only in proper names, so as not to view unnecessary links. At the request of the “blacksmiths,” for example, documents will be found that mention both the blacksmiths and the Kuznetsovs.

Narrow your search using a few keywords.

If the desired address is not among the first twenty found addresses, you should modify the request.

Each search engine uses its own query language. To get to know him, use the built-in help of the search engine

Large sites may have built-in information retrieval systems within their web pages.

Requests in such search engines, as a rule, are built according to the same rules as in global search engines, however, getting to know the help here will not be amiss.

Advanced Search

Search engines can provide the user with a mechanism to formulate a complex query. Following a link Advanced Searchmakes it possible to edit search parameters, specify additional parameters and choose the most convenient form for displaying search results. Below are described the parameters that can be set during an advanced search in the Yandex.Ex and Rambler systems.

Some search engines (for example, Yandex) allow you to enter queries in a natural language. You write what you need to find (for example: ordering tickets for a train from Moscow to St. Petersburg). The system analyzes the request and gives the result. If it does not suit you, go to the query language.

For most individual users, affordable access to the Internet is through dial-up telephone channels at speeds up to 56 Kbps. Connection via dial-up telephone lines is provided. providers   Internet services.

When choosing a provider, it is advisable, firstly, to get information from him about the number and throughput of channels connecting him to the Internet. The more such channels and their bandwidth, the more reliable and faster your work on the Internet. Secondly, it is useful to know how many input telephone lines a provider has. The larger it is, the faster you can reach him. Finally, thirdly, in order to save money, you need to find out the payment scheme and the cost of connection.

Modulation rate and data rate.   To connect a computer to telephone line   using a modem. At the computer output, the data is presented in the form of sequences of electrical pulses that the modem converts to a modulated analog signal.

In the simplest case, amplitude modulation is performed when the amplitude of the carrier (an analog sinusoidal signal) changes abruptly and takes one of two possible values. In the process of frequency modulation, the frequency jumps analog signal, and with phase modulation - the phase of the signal. In each of these cases, there are two possible states of the carrier analog signal and, accordingly, each change carries 1 bit information.

Modulation rate   characterized by the number of switching from one analog signal to another in 1 second and is measured in baud. For example, if in one second the analog signal changes 9600 times, then the modulation speed is 9600 baud. However practically important characteristic   modems are data ratemeasured in bits per second   (abbreviated bit / s).

If only one type of modulation is used (for example, only amplitude modulation), then 1 baud corresponds to 1 bit / s and the data transfer rate in the above case is 9600 bit / s. If two types of modulation are implemented simultaneously (for example, amplitude and frequency), then each time the analog signal changes, one of four states is selected and, therefore, each such change carries 2 bits of information.

Data transfer rate standards (modem communication protocols).   The data rate is determined by the used speed and modulation method, which are standardized modem communication protocols   so that modems can "understand" each other. The first “ancient” modem protocol enabled modems to exchange information at a speed of only 300 bps. Then, as modem communications improved, various firms developed various higher-speed “proprietary” protocols, which were then usually standardized.

In 1994, the standard V.34 protocol was adopted, which provides a data transfer rate of up to 28,800 bps, in 1996 it was improved, received the name V.34 + and began to provide a transmission speed of up to 33,600 bps.

Modern modems can provide a transmission speed of up to 57,600 bps, which is achieved using proprietary x2 or K56Flex protocols and the standard V.90 protocol. Usually modern modems also support several previously adopted protocols, which allows you to save the ability to exchange information with previously released modems.

In order to determine the protocol by which two modems will exchange information, first between them special signals are exchanged, with the help of which the modems tell each other a list of supported protocols. The process of establishing a connection (in English, handshaking, i.e., shaking hands) is accompanied by a characteristic whistle of various frequencies, which can be heard from the modem's speaker. As a result, modems choose the most high-speed protocol for information exchange, of both modems.

Browsers   Global computer network   The Internet includes more than 100 million servers that host billions of Web pages. Web pages using hyperlinks are interconnected and form the World Wide Web. For travel on the World Wide Web are used special programs - browsers. The browser loads the Web page and displays it according to the tags of the Hypertext Markup Language (HTML). Browsers exist for everyone. operating systems, for example, for MS-DOS - Arachne, for Windows - Microsoft Internet explorer, Netscape Communicator, NeoPlanet, Opera, etc.

If start page   Since the site’s name is index.htm, you can omit its name in the URL (by default, a page with the name index.htm is loaded into the browser from the specified directory).

For information retrieval   the Internet uses special search servers that contain constantly updated information about Web sites, files, e-mail addresses and other information resources of the Internet. Different search engines can use various mechanisms   search, storage and provision of information to the user.

Internet search engines can be divided into two groups: general-purpose search engines and specialized search engines.

General purpose search engines.   General-Purpose Search Engines Locate Documents on the World Wide Web by keywordsthat are entered in the search field and / or using the hierarchical system directories.

Search engines. Auto fill   search engine databases are made by robotic systems (Search Engines). A special robot program called a spider constantly surfs the Internet in search of new informationwhich she brings to the database. The database contains URLs and indexed information associated with these addresses.

A powerful search engine crawls the entire Internet in a few days. At the same time, a new index is compiled - an inventory of available resources. With each new crawl, the index is updated and old invalid addresses are deleted.

When searching by keywords, one or more keywords are entered in the search field, which, according to the user, are the main ones for the document to be searched. You can also use complex queries that use logical operations, patterns, etc.

Catalogs. Directories are compiled by editors who review each new site before it is included in the index. In the process of filling directories, site developers themselves can participate when registering in the search engine. Directories are usually organized according to subject classification.

The quality of systematization of sites is higher than that of search engines, but people cannot keep up with the pace of expansion and change of the Internet: the index of the popular Yahoo! contains just over a million entries.

The directory interface contains list of sectionsinto which links to the URLs of the most important documents are grouped. Each link is usually annotated, i.e. contains short description   content of the document.

The most popular general-purpose search engines on the Russian-language Internet (Runet) are Yandex (www.yandex.ru), Rambler (www.rambler.ru) and Aport (www.aport.ru), and in English - Yahoo! (www.yahoo.com).

Important indicators of the quality of a search server are:

• database size (number of documents);
• internet crawl speed by software robot (the speed of updating information in the database is associated with this);
• indexing algorithm (only for keywords on a web page or throughout the text);
• advanced search capabilities using the query language;
• directory system structure.

1. Efimova O., Morozov V., Ugrinovich N. Course computer technology   with the basics of computer science. Tutorial   for high school. - M.: Publishing House AST; ABF, 2000
2. Ugrinovich N. Computer science and information technology. Grade 10-11- M .: Laboratory of Basic Knowledge, JSC Moscow Textbooks, 2001
3. The Internet. Encyclopedia. Second Edition./ Ed. L. Melikhova. - S.-Pb., M., Kharkov, Minsk: Peter, 2001.

Tasks and tests on the topic "Computer communications. Networks: global and local. Internet. Structure, addressing, basic types of services"

• Local and global computer networks

  Lessons: 2 Tasks: 9 Tests: 1

• World Wide Web - Communication technology   Grade 9

  Lessons: 4 Tasks: 9 Tests: 1

• Work 1 presents three themes that underlie the course " Information Technology". We hope that you already have minimal experience working with a computer and get acquainted with its device back in high school.

  The topic "Computer Communications. Internet" is of great interest in recent times, many young people spend almost all their free time on a global network. I would like to remind you that the masterly possession of the Internet implies not only the ability to “surf” the network and visit interesting “chats” from time to time, but also to understand the principles of organizing information on the global network, to understand its structure, protocols, be able to configure the browser and mail programs, Know and comply with the ethics of working on the Internet. And of course, use the network for the most important of its purposes - to expand its horizons.

  We did not consider the technology of creating Web sites in this course, believing that the minimum knowledge for creating a home page can be gleaned from additional literature. The creation of sites on a professional level requires some preparation, which is based on skills in working with text and graphics, as well as programming skills.

  The topic "Logic" usually causes some bewilderment of students, not everyone understands the importance of studying this topic. I would like to note that knowledge of logic is important not only as a basis for further study of programming languages \u200b\u200band principles of working with databases, but also as a "simulator" for the development of a special type of thinking. A person who has succeeded in studying logic has huge advantages in communication. It’s very flattering to hear: “Logically”, “there is logic in your reasoning”.

Search for information on the Internet. General purpose search engines. Search by keywords and in a hierarchical directory system. The formation of mail messages. Signature in the email. Work with the address book. Insert an address into a message.

Agreement on the use of site materials

Please use the work published on the site solely for personal purposes. The publication of materials on other sites is prohibited.
This work (and all others) is available for download for free. Mentally, you can thank its author and the site team.

Send your good work in the knowledge base is simple. Use the form below

Students, graduate students, young scientists who use the knowledge base in their studies and work will be very grateful to you.

Similar documents

The development of the information environment. Key principles of the Internet. Russian and English terms Internet. Web page extensions. Names of test files. Internet URL Rambler search engine page. Search for keywords on the Internet.

test, added on 10/04/2011


Internet and its features. A common and inexpensive way to connect to the Internet. The scheme of information transfer via TCP / IP. Characteristics of addresses of different classes. Search engines, methods for searching and downloading information on a global network.

term paper, added 09/25/2013


The essence and principle of the global Internet. Search for information on parameters in google system. Specialized information retrieval systems: WhoTam, Tagoo, Truveo, Kinopoisk, Catch-Umov. Appropriate use of search engines.

presentation, added 02.16.2015


The concept of the Internet system, usage, network size, number of subscribers and users. Search engines, an approach to collecting information about Internet resources. Modern search engines. Work with resource catalogs, saving information on the Internet.

abstract, added 02.12.2010


Techniques for finding information on the Internet. Search for a known address, constructing the address by the user. Special information retrieval systems: classification (headings) and dictionary. Search for information resources in various directions.

abstract, added 03/03/2010


The information revolution that society is currently experiencing. Conducting a structural analysis of documents. Search for analog information in system areas. Search for information over the Internet. Types of search resources: directories and search robots.

term paper, added December 16, 2012


The concept of "information". Interactivity Information Search. The Internet as the main means of interactive information retrieval. History of the creation of the Internet. Internet access. Search resources. Types of search engines. Email.

term paper, added 02.15.2007

So, specialized search engines are search engines focused on finding information on a specific topic. They have advantages over general-purpose search engines. But, of course, there are also disadvantages.

In order to find the required information on the Internet, you need to know either the address of its location (for example, the address of an html page or file), or an Internet user who can provide information. If we do not know either the address or the person who could help us, then we should go to the questions "How can I find out the address of the information?" or "How to find someone to help us find information?" However, the capabilities of the Internet should not be overestimated. The best results can be obtained by combining online and offline methods of finding information.

Where are we looking?

Information can be posted on web servers, blogs, in news, in books, in dictionaries, in goods, on geographical maps, in directories of organization addresses, among posters of theaters and museums, in television programs, in catalogs, in Wikipedia, in Internet archives , in peer-to-peer networks, in databases, in web bookmarks or in rating systems. Therefore, it is better to decide in advance where we will begin our search.

information sources;

blog Search

search in the news;

google News

yandex news;

search for books;

search in pictures;

search in goods;

map search;

search for a poster;

wikipedia search ...

How are we looking?

Search methods depend on how we answered the first two questions. Search can be carried out in search indexes, by posting your own publication on a specific topic, through experts, etc.

information search cards;

search indexes;

query language in search indexes;

search on sites of legal systems;

search engines:

@ MAIL.RU

Rambler

Applications

search tips

Search methods on the Internet and through the Internet are many. Therefore, the search for information is reduced to the choice of search methods that require their assessment by the task. The success of the search depends on the knowledge of possible methods and skills of owning them, knowledge of ethnic languages \u200b\u200bin which this information can be presented. Thus, search planning comes down to three questions: “What are we looking for?”, “Where are we looking?”, “How are we looking?”.

What are we looking for?

Search queries are explicit and implicit. In explicit questions, the search object is specifically indicated. In implicit issues, for example, "what is the weather today», « is something important happening now», « is it possible to drive around the city", Or by A. S. Pushkin in" The Tale of the Dead Princess and the Seven Knights ":

My light, a mirror! tell me

Yes, tell the whole truth:

I am sweeter in the world

All blush and whiter?

the search object is not specifically indicated.

Search queries are also divided according to the required search system. The first group of search engines is intended only for a linear search of information, that is, for detecting fragments similar to a given one in texts. Therefore, the request should contain a fragment of text. The second group of systems allows you to select data on the relationships between objects, which requires an indication in the request for communication between various objects.

To plan your search:

Define a search object,

formulate what information needs to be found.

If it is not possible to unequivocally answer this question, then the search should be divided into tasks with different objects. In planning the search should also determine the ratio of the types of information in the search task.

Example:    if you need to introduce some company, then not only the standard characteristics of the company (data on turnover, customers, etc.), but also information on the relationships of its top officials can become useful. And vice versa - an individual can be characterized through the company that he owns or in which he works.

It is necessary to determine the possible file formats in which the required information may be contained. It can be an html page, a text document in txt, rtf, odt, doc or docx formats, pdf document, presentation in odp, ppt or pptx formats, spreadsheet   in formats

browsers

panel quick access   to google search engine

quick access panel to the Yandex search engine

questions and tasks

Google news

In 2002, Google launched a new google service   News, the essence of which is to collect information from the world's most popular sources of information - BBC, CNN, Guardian, Washington Post and others - with the subsequent publication of news headlines, grouped in several categories and importance.

Currently, news services are available in almost all Russian search engines.

Yandex. news

Yandex. News is updated in real time 24 hours a day.

Annotating stories in this service also happens automatically. Actual headings and annotations are formed computer program. In this case, the texts of annotations are selected so as to supplement the information from the title.

On the site, search is available not only for the latest news, but also in a huge archive informational messages   since 2000. In addition, based on the analyzed publications, a rating of the most popular people in the media is compiled.

Blog Search

The rapid development in recent years of private online diaries, the so-calledblogging , is also reflected in search services. In 2004, the Yandex search engine began testing a service that allows you to search blogs. In March 2006, the service was updated and is now essentially an indicator of the public opinion of the Runet.

Book Search

In October 2004, at the book fair in Frankfurt, Google introduced the Google Print service. On November 17, 2005 its name was changed toGoogle book search . This service performs a full-text search on books that Google crawls and stores in its digital database.

Dictionary Search

The purpose of the Yandex.Dictionaries service is to provide Internet users with the highest quality, reliable and relevant information about all areas of human life. Sources of such information are universal and thematic encyclopedias, reference books, various dictionaries of the Russian language and foreign languages.

In September 2006, Yandex launched a program to create an electronic library of reference books. As part of this program, the company acquires rights, digitizes and publishes on the Internet the most interesting dictionaries and encyclopedias in various fields of knowledge. The project provides for the regular receipt of new dictionaries and encyclopedias.

Search in pictures

Yandex service automatically collects pictures in standard graphic formats   (jpeg, gif and png) located in RuNet.