Searching for information on the Internet (grade 9). Presentation on the topic "ways to search for information on the Internet" Methods to search for information on the Internet presentation

Lesson "Searching for information on the Internet"
Target:
Master the basic methods of searching the Internet; know how to present information on the Internet.
be able to navigate the logical levels of information organization
Tasks:
Educational – developing skills in searching for information on the Internet;
Developmental – developing students’ ability to navigate the logical levels of information organization.
Educational – instilling in students responsibility for business and interest in computer science.

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Searching for information is one of the most popular tasks in practice that any Internet user has to solve. There are three main ways to search for information on the Internet: Specifying the page address. Navigation via hyperlinks. Contacting a search engine (search server).

This is the most quick way search, but it can only be used if the exact address of the document or the site where the document is located is known.

This is the least convenient way, since with its help you can search for documents that are only close in meaning to the current document.

Search server addresses are well known to everyone who works on the Internet. Currently, the following search servers are popular in the Russian-speaking part of the Internet: Yandex (yandex.ru), Google (google.ru), Rambler (rambler.ru) and some others.

Principle of operation search engine. Ease of use. Complexity of the query language. Speed ​​of work.

Index search engines working in automatic mode updating their information, browsing the contents of servers on the Internet, indexing all the information contained in them and entering information about the location of words on website pages into their databases. Catalog search engines contain a thematically structured catalog of servers and are most often updated manually.

Information need - information and data needed by the user in this moment. Relevance property is a set of documents that matches the query. Search completeness – reflects the ratio of relevant responses to the number of all possible documents, satisfying the information needs of the consumer. Search accuracy – expresses the ratio of the totality of relevant responses to the number of all returned documents.

Take into account the features of natural language. Avoid spelling errors. Avoid searching for one word, use a necessary and sufficient set of words. Do not write in capital letters. Exclude unnecessary words from the search.

Language Syntax Meaning Example! Prohibition of enumerating all word forms! pedagogical system (the words pedagogical systems will be excluded from the search) + Mandatory presence of the words in the found documents Teachers' Council on + Friday (pages where the word not only teacher's council occurs must be selected) but the obligatory condition is the presence of the word "Friday" & Mandatory occurrence of words in one sentence Pedagogical & system "" Search for stable phrases "pedagogical system" (the strict sequence of words is taken into account, the word "pedagogical system" will be excluded)

– What are the main ways to search for information? – What two types of search engines do you know? – Name the most popular Internet search engines. – What are the rules for searching for information? - What are query languages ​​used for?

How many countries and which ones are included in the European Union? How many domes are there on St. Basil's Cathedral on Red Square? In what year was it invented? computer mouse? On which floor in the Hermitage does the collection of tapestries hang? How many floors are there in the Main Building of Moscow University? What does the term “entropy” mean from the point of view of information theory? What is the maximum depth of the Black Sea?

Preview:

Lesson "Searching for information on the Internet"

Target:

Master the basic methods of searching the Internet; know how to present information on the Internet.

be able to navigate the logical levels of information organization

Tasks:

Educational– developing skills in searching for information on the Internet;

Developmental – development of students’ ability to navigate the logical levels of information organization.

Educational – instilling in students responsibility for business and interest in computer science.

Lesson type:

learning new material.

Forms of training:

Frontal, individual.

Teaching methods:

Verbal, visual, practical, partially search-based.

Equipment:

1. A computer with Internet access, a multimedia projector, an office equipped personal computers with Internet access at the rate of 1 student - 1 computer.
2. Presentation for the lesson

Brief lesson plan:

1. Organizational moment, TB – 5 min.
2. Technologies for searching information on the Internet – 30 min.
3. Work in groups to search for information on the Internet – 35 min.
4. Messages from students of search results – 10 min.
5. Summing up the lesson – 10 min.

During the classes

1. Organizational moment.

Teacher : Good afternoon guys. Today we have a lesson in which you will learn how to search for information on the Internet, learn about search engines that make it easier to find the information you need. But to successfully achieve our goal, let's answer a few questions from the topics you have studied previously and repeat the safety rules when working at a computer:

1. What types computer networks do you know?
2. What is the Internet?
3. What programs for accessing the Internet do you know? What is the common name for these programs?
4. Why is the Internet so popular in today's world?

Thanks for answers. Well done!

2. Study a new topic

Teacher : And now we’ll talk about searching for information on the Internet(Appendix 1, slide 1).

Very often there is a need to search for the required information on various topics. To do this, you can use the necessary literature. But the most effective and quick method is searching for information on the Internet. But having a computer and Internet access does not guarantee that a person will be able to find necessary information quickly and completely.

To search the Internet, you can use specialized service services that allow you to find a particular document using keywords. They are called search engines. In addition to search engines, there are metasearch engines. They do not have their own search engines, but use the capabilities of other search engines.

Search engines are presented to users in the form of web pages with easy navigation. Simply enter the system address, and the required page will be presented to your service. Another feature built into the browser is presented on the panel in the form of a “Search” button

Tell me what methods of searching for information do you know?

There are three ways to search for information on the Internet(Appendix 1, slide 2):

1. Specifying the page address.
2. Navigation via hyperlinks.
3. Contacting a search engine (search server).

Let's look at each of them:

– (Appendix 1, slide 3):Specifying the page address is the fastest way to search, but it can only be used if you know exactly the address of the document or site where the document is located.

– (Appendix 1, slide 4): Navigating through links – This is the least convenient method, since it can be used to search for documents that are only close in meaning to the current document.

But this method is very simple and suitable for a novice user.

Using hypertext links, you can travel endlessly to information space Network, moving from one web page to another, but if you consider that many millions of web pages have been created in the world, then it is unlikely to be possible to find the necessary information on them in this way.

– (Appendix 1, slide 5):This is where special search engines (also called search engines) come to the rescue. Search server addresses are well known to everyone who works on the Internet. Currently, the following search servers are popular in the Russian-language part of the Internet: Yandex (yandex.ru), Google (google.ru), Rambler (rambler.ru) and some others.

(Appendix 1, slide 6):What is a search engine?

There are several thousand search engines on the World Wide Web. Each system has its own advantages and disadvantages. The criteria for choosing a search engine can be the following characteristics:

1. The principle of operation of the search system.
2. Ease of use.
3. Complexity of the query language.
4. Speed ​​of work.

(Appendix 1, slide 7):There are 2 main types of Internet search engines: index and classification (catalog).

Index search engines, working in automatic mode of updating their information, view the contents of servers on the Internet, index all the information contained in them and enter information about the location of words on website pages into their databases.

Catalog search engines contain a thematically structured catalog of servers and are most often updated manually.

(Appendix 1, slide 8):Basic concepts and characteristics of search results.

Information need– information and data needed by the user at the moment.

Relevance property– a set of documents that corresponds to the request.

Search completeness – reflects the ratio of relevant responses to the number of all possible documents that satisfy the consumer’s information need.

Search accuracy – expresses the ratio of the totality of relevant responses to the number of all issued documents.

(Appendix 1, slide 9):Now let's try to derive rules for searching information on the Internet?

1. Take into account the features of natural language.
2. Avoid spelling errors.
3. Avoid searching for one word, use a necessary and sufficient set of words.
4. Do not write in capital letters.
5. Exclude unnecessary words from the search.

(Appendix 1, slide 10):The concept of a query language.

Now let's answer a few questions(Appendix 1, slide 11):

– What are the main ways to search for information?

– What two types of search engines do you know?

– Name the most popular Internet search engines.

– What are the rules for searching for information?

What are query languages ​​used for?

3. Practical activities on a PC:

Teacher : Now let’s sit down at the computers and do the practical work.(Appendix 1, slide 12).While doing the work, the teacher controls the search process so that students do not get carried away by idle reading of sites, since they need not only to find the necessary information, but also to compare search engines; helps correct the wording of the request if the student did not find any of the desired documents.

1. How many countries and which ones are included in the European Union?
2. How many domes are there on St. Basil's Cathedral on Red Square?
3. In what year was the computer mouse invented?
4. On which floor in the Hermitage does the collection of tapestries hang?
5. How many floors are there in the Main Building of Moscow University?
6. What does the term “entropy” mean from the point of view of information theory?
7. What is the maximum depth of the Black Sea?

After completing the task, students report the results of their information search.

At the end of the lesson, the teacher sums it up and evaluates the students’ work.

Teacher : The lesson is over. Thank you for the lesson!

TRANSMISSION OF INFORMATION IN COMPUTER NETWORKS

• How is a computer network organized?
• E-mail and other computer network services.
• Hardware and software networks.
• Internet and World Wide Web.

The purpose of the lesson: introduce students to various Internet search resources, information search methods, and develop students’ skills in using search services to search for information in World Wide Web .

To teach how to apply the knowledge and skills acquired in computer science lessons to organize a search for specific information on the Internet.

For organization convenient search for web pages with the necessary data can be specified in the browser page address or contact search services .

By operating principle there are several types search services .

The most common are:

web directories

search engines .

Web directories

(other name thematic catalogs ) contain a database of links to websites, divided into separate thematic sections.

Site registry

Web directories there are:

universal , containing links to websites from different parts of the world with a variety of topics;

territorial , covering web resources of a country, region or city;

specialized , containing links to websites of a certain focus - literary, scientific and technical, commercial, educational, etc.

To perform a search, select the heading names sequentially, narrowing the search area.

Artificial intelligence

Several years ago, registration in web directories was the most effective method for promotion websites , but gradually search engines became smarter and catalogs lost ground in many positions.

But even at the moment, many people use this method for promotion, because search engines quickly index directories and provide little traffic.

P search systems

Another type of search services - P search systems, which are also called index databases , or search indicators .

Search system is a website that allows you to search for the necessary information on the Internet.

Database search engines contain many more links to web pages than databases thematic catalogs .

This is achieved due to the fact that web pages are processed not by people, but by special programs called search robots .

These programs scan the content of web pages, determine the words that appear most often in the text, and store the results of processing the content of the pages in a database search engine .

Search engines can compare with a help desk whose agents go around businesses collecting information into a database

Spider robots scan content

Web pages and create a base on which the search is carried out.

RELEVANCE- degree of correspondence between the request and what was found.

To search for information using keywords you must enter keyword or a combination of several words in a special search engine query input line

Check out some search engines.

SOME OPERATORS SEARCH IN GOOGLE

1. OPERATOR " + »

There are situations when you need to forcefully include in the text a word that may have different spellings. For this purpose it is used operator "+" before a required word . Suppose if we have a request One Houses I , as a result of the request we will have unnecessary information about " One Houses II ", " One Houses III "and just a little about" One Houses I ". If we have a request like Home alone +I , the result will be information only about the movie" Home Alone I ".

2. EXCEPTION WORDS FROM REQUEST " - ":

As you know, information garbage is often encountered when composing a request. To remove it, the standard exception operators are used - logical "NOT" . Google has this operator presented sign « minus " Using this operator, you can exclude from search results those pages that contain certain words in the text.

Example, BLACK TEA - GREEN

GREEN

3. SEARCH ACCURATE PHRASES (""):

In practice, searching for an exact phrase is required either to search for the text of a specific work, or to search for specific products or companies in which the name or part of the description is a consistently repeated phrase.

Google allows you to enter no more than 32 words .

4. TRUNCUTION WORDS " * "

Sometimes you need to look for information about a word combination in which one or more words are unknown. For these purposes, instead of unknown words, the operator is used "*" .

Those. "*" - any word or group of words.

5. OPERATOR CACHE

The search engine stores the version of the text that is indexed by the search spider in a special storage format called cache . A cached version of a page can be retrieved if the original page is not available ( for example, the server on which it is stored is not working ).

You can create a request that will immediately return a cached version of the page with specific address: cache:page_address , where instead of “page address” is the address of the page saved in the cache.

If you need to find any information in a cached page, you need to write a request for this information separated by a space after the page address.

Example :

cache:http://www.livejournal.com/

There should be no space between ":" and the page address!

6. OPERATOR FILETYPE

As you know, Google indexes not only html pages.

If, for example, you needed to find some information in a file type other than html, you can use the operator filetype , which allows you to search for information in a specific file type ( html, pdf, doc, rtf... ).

Here is an example of a pdf search: filetype:pdf

7. OPERATOR DEFINE

This operator acts as a kind of explanatory dictionary, which allows you to quickly get the definition of the word that is entered after the operator.

For example : define:computer science

8. String Google search can be used as a calculator by entering an example that needs to be calculated: (7+3*5)/11=

9. This search engine also allows convert units of measurement quantities from the English system of measures to the metric system and vice versa: 9.5 yards in centimeters .

10. In addition to converting units of measurement, you can also convert currency different countries , To example: 200 US dollars in rubles.

The ability to correctly formulate a request and knowledge of some subtleties and tricks will save you from tedious browsing through unnecessary and uninformative sites.

Searching the Internet can be fast and effective - if you know how to search correctly !

Following some specific rules

when searching for information on the Internet

Formulate it correctly search query. It should not be too short nor too long. The optimal length of a search query is 2-3 words.

If you are not satisfied with the result, try changing the query by rearranging the words in the query or using synonyms.

To find an exact phrase or quote, enclose your search query in quotation marks.

Typically, entering a qualified query is more efficient than searching through the results.

Try not to formulate your search query as a question to the search engine.

Pay attention to website domains from search results so as not to accidentally click on a suspicious link.

Use more than one search engine. From different search engines different principle rankings, so what was not found in one may be found in another.

Use additional search technologies of search engines (search by images, search by region, search by blogs, advanced search, etc.).

Use the search capabilities of your browsers. For example, the Ctrl+F key combination enables page search.

Please note that search results are dynamic and may change after a few days or even hours. Therefore, if you find a useful link, you should immediately add it to your bookmarks: next time the result of an Internet search may turn out to be different, and you will simply lose the site you once found.

Search

information on the web

Internet

Searching for information on the Internet is carried out using special programs processing requests - information retrieval systems (IRS).

An information retrieval system is an applied computer environment for processing, storing, sorting, filtering and searching large arrays of structured information.

There are two types of IPS:

1. Documentographic. In documentographic information retrieval systems, all stored documents are indexed in a special way, that is, each document is assigned an individual code that makes up a search image. The search is not based on the documents themselves, but on their search images. This is how books are searched for in large libraries. First, they look for the card in the catalog, and then, using the number indicated on it, the book itself is found.

2. Factual. Factual information systems store not documents, but facts related to any subject area. The search is carried out using a sample fact.

In Russia, the largest and most popular search engines are:

• "Yandex" ( www.yandex.ru)
• "Rambler" ( www.rambler.ru)
• "Google" ( www.google.ru)
• "Mail" ( www . mail . ru)

Web server- this is the computer on which it is installed

special software.

Web site- this is a place on the web server.

The Internet has adopted a numeric addressing system.

Computers prefer numbers ( 213.180.204.11 ), and people are names ( yandex.ru), since names are easier to remember.

Therefore, the Internet was introduced domain name system .

educom.spb.ru

Third level domain

tells the name

organizations, on

which is registered

this domain

Top level domain:

means that the site

Registered in the Russian Federation

The entire sequence of characters

used in an address is called URL

Second level domain

means that the site

registered in

St. Petersburg

Uniform Resource Locator (URL - Uniform Resource

Locator ) - uniform locator (determinant

location) of the resource.

Previously called Universal Resource Locator -

universal resource locator.

URL is a standardized way of writing the address of a resource

on the Internet.

URL was invented by Tim Berners-Lee

in 1990 within the walls of the European

nuclear research council

in Geneva, Switzerland.

URL has become a fundamental innovation

in the Internet.

The URL was originally intended to

location designations

resources (most often files) in

World Wide Web.

Nowadays, URL is used to designate the addresses of almost all

Internet resources.

Search types:

• Search by URL

• Search engines

Search engines

Search engines- This automatic systems, polling servers connected to global network, and storing in their database information about

available on data servers.

ROBOT

INDEX

PROGRAM

TREATMENTS

QUESTIONS

Russian search servers:

• "Yandex" - www.yandex.ru;
• "Rambler" - www.rambler.ru;
• "Mail" - www . mail . ru ;
• "Gogo" - www.gogo.ru.

Foreign search servers:

• Alta Vista - www.altavista.com
• Fast Search - www.alltheweb.com
• Northern Light - www.northernlight.com

Search technology

search engines

2. Search by keywords

Search by keywords

The simplest and most effective search is to search by keywords.

The basic search algorithm is as follows:

enter keywords V request field(For example, train schedule ), press the button Find .

Query language syntax

In system Yandex there is a special query language, which is more difficult to use than the advanced search form, but when used you can get the best results.

Search query entered into the search field, it may contain keywords And Special symbols , allowing you to establish relationships between these words and enter Extra options. Most of these symbols are presented in the table below.

Syntax of the Yandex system query language

Syntax

What does operator mean?

operator

space or &

Logical AND (within a sentence)

Example request

physiotherapy

Logical AND (within document)

Logical OR

recipes && (processed cheese)

photo | photography | snapshot | photographic image

Mandatory presence of the word in the found document

Grouping words

To be or +not to be

Binary operator AND NOT (within a sentence)

~~or_

(technology | production) (cheese | cottage cheese)

banks ~ law

Binary AND NOT operator (within document)

Paris guide ~~ (agency | tour)

Distance in words (minus (-) - back, plus (+) - forward)

suppliers /2 coffee music /(-2 4) education vacancies ~ /+1 students

Search for a phrase

&&/(n m)

"little red riding hood" Equivalent to: red /+1 riding hood

Distance in sentences (minus (-) - back, plus (+) - forward)

bank && /1 taxes

Specialized information retrieval systems

On the Internet there are search engines for certain areas:

Ktotam.ru– searching for information about people

tagoo.ru– music search

kinopoisk.ru– search for movies

ebdb.ru–finding books from electronic libraries

ulov-umov.ru- job search

Appropriate use of search engines

• Today, young people view the Internet and computers as a means of entertainment.
• Internet resources are varied. They have both helpful information, and harmful.
• Internet information retrieval systems from Internet resources have the ability to find any requested information. Because search engines search using keywords.
• Whatever query the user asks, he will receive such information.
• It is necessary to remember that the information received is not always truthful, useful or correct.
• Information retrieval systems should be used only as expediently.
• You cannot distribute or use false, immoral and compromising information

"Searching for scientific information on the Internet" Stepanova Tanya Master's degree 1st year

When working online, it is useful to rely on the opinion of professionals who have previously gone through the same search path, done the rough work and compiled tips, guides, lists of useful pages and sites for colleagues. Specialists can be a good help. search engines that select web resources worth attention using a given algorithm.

Main positive points: Large catalog of accessible chemical journals There are patent databases There are also links to articles and reference books

A definite plus: quick navigation through reference books A wide variety of reference material There are different sections on chemistry

Windows Live Academic Beta version of the academic search engine from Microsoft. Designed to search for scientific articles both in open sources and in archives of publications with paid access. Currently, articles on physics, chemistry, computer technologies, electrical engineering and related disciplines.

Chemweb is the largest online chemistry portal in the world. Contains information on research in the field of chemistry and chemistry. industry. Topics: analytical chemistry, biochemistry, catalysis, electrochemistry, fuel, inorganic chemistry, chemical materials, organic chemistry, pharmacology, physical chemistry, polymers. Access to 350 journals and databases.

Nigma Search engine for chemical data Substances can be written both using names and in the form of formulas. For the entered substance, the system will try to find reactions with their participation. In addition to the molecular formula, the system provides the ionic formula. The system will tell you why the reaction is impossible

List of links used: