Information retrieval toolsWWW. Useful World Wide Web Addresses Most Common Search Engines on the World Wide Web

05.11.2019 In contact with

Back forward

Attention! The slide preview is for informational purposes only and may not represent the full extent of the presentation. If you are interested in this work, please download the full version.

Goals:

understand the basic principles of organizing the search for information on the Internet.
develop algorithmic thinking, the ability to highlight the main thing, expand the horizons of students by introducing new terms;
formation of information search skills on the Internet;
to cultivate a culture of communication: student-student, teacher-student

Tasks:

Familiarity with the concept of WWW
Web page, Web site
Internet page addressing
Familiarity with the capabilities of search engines, search queries.
Use the search and selection of information in practical activities and everyday life

Hardware and software: interactive whiteboard, projector, presentation for the lesson, cards - assignments, a set of assessments.

Lesson type: learning new material.

During the classes

I. Organizational moment.

II. Knowledge update. Presentation of new material.

- Hello guys. Today we will take you on a journey...

Look carefully at the slide. Where do you think we will go?

On a journey through the Internet.

The screen shows an approximate graphic representation of the links between Internet networks. Only links between servers are shown.

What does this picture look like? (To the starry sky, to the web.).

Lesson topic: “WWW. Journey on the World Wide Web”.

But before we cruise around the Web, we will get acquainted with the concept of WWW, Web page, Web site, browser, search engine, and then move on to the practical part: we will work with search engines, make queries, find the necessary information and apply it in practice.

What is the Internet? The Internet is a worldwide system of interconnected computer networks for storing and transmitting information. The World Wide Web is based on the Internet

WWW - what does this abbreviation mean? (World Wide Web, WWW)

World Wide Web (WWW, Web) - worldwide NETWORK (web)

WWW is a global repository of information that exists on the technical basis of the INTERNET (after all, there are more than 2 billion Internet users)

WWW - the union of numerous resources distributed around the world;

WWW is an organization of information resources provided with hyperlinks.

WWW - contains information of a very different nature: news, scientific, technical, educational information, advertising of goods and services, resources for leisure and entertainment, communication through social networks, portals and forums, and much more. The life of a modern person is now impossible to imagine without the Internet.

Anyone can post information online, and the whole world will have access to this information!

Information on the WWW is organized as Web pages . For example, let's open the website of our school www.schuv1996.mskobr.ru.

website - These are several Web pages that are interconnected by content. In the texts posted on the pages of sites, keywords - hyperlinks - can be highlighted.

The address of any file on a worldwide scale is determined unified resource pointer - URL. The URL is a standardized string characters indicating the location of a resource, document or part of it on the Internet, and consists of three parts.

Address structure:

protocol name for accessing the Internet service;

The name of the server that hosts the resource and runs the Internet Service server application. This is where we often see the abbreviation www;

the full name of the file that is stored on the server.

www.schuv1996.mskobr.ru.

http:// protocol

schuv1996.mskobr.ru - server

news/ - page file

A huge number of hypertext electronic documents stored on WWW servers form a kind of hyperspace of documents between which movement is possible.

But special programs help the user navigate the “web”. (Web browsers; browse view, study)

What browsers do you know?

Is there any information storage system on the Internet, is it possible to “get confused” in the web? Is it chaos or is there some kind of system, logic?

In order not to get confused, you need to know where and how to extract the necessary information, you need experience in search work. How to search for information:

By specifying the address of the document (wikipedia.org)
By navigating through a web of hyperlinks
By using search engines. YANDEX, RAMBLER

SEARCH ENGINES (search technology)

All information retrieval systems on the World Wide Web are located on special servers. Every day they serve a huge number of customers. The action of search engines is based on the constant, consistent study of all pages of all sites. For each document, page, there is a certain set of keywords that reflect the content of the page. When a query is received, the search engine generates a list of pages that match the search criteria. Found documents are ordered depending on the location of keywords, the frequency of their occurrence in the text, etc.

What search engines do you know? ( GOOGLE, YANDEX, RAMBLER)

Search engines usually have three operators: "logical AND", "logical OR" and "logical NOT". The "logical AND" operator is indicated between the keywords if it is necessary to return documents containing all the searched words. “Logical OR” is used when it is necessary to search for documents containing at least one of the keywords associated with this operator. The "logical NOT" operator is necessary to exclude from the list of documents in which there is a word preceded in the query by this operator.

When starting a search, the user enters one or more keywords and selects the search type.

If the search is difficult, try changing the query logic, pick up better synonyms

III. Practical part.

Students are divided into micro-groups.

1 stage of work

You are invited to complete the crossword "History of the INTERNET" ( Attachment 1), using the World Wide Web and search engines known to you.

Everyone is looking for the answer to the first question of the crossword puzzle, but on different search servers.

Let's compare the number of found links to documents and sites for the same query. - Which search engine gave more links?

Whoever found the answer to the question raises his hand and fills in the crossword puzzle on the Smart interactive whiteboard. Students find the right answer and write it down on the interactive whiteboard where the presentation is projected. As a result of the work, all cells of the crossword puzzle are filled.

Notice which keyword is in the highlighted cells? - Internet! Correctly. – So, with the first stage of this task, we coped with it, working together.

Stage 2. Card work

Find answers to the following questions ( Annex 2) and save them in your folders (work in micro-groups):

1) What day is considered the birthday of the Internet in Russia and why?

2) When and where was plombir ice cream invented?

3) Where and when did chocolate appear?

4) What is the brightest star in the night sky?

5) Why is the Black Sea called "Black"?

6) Which country is the smallest? Give it a brief description.

7) When and where were the first Olympic Games held? Give a short description.

Save the information as text and pictures in your folder.

Save information from downloaded Web pages in a variety of ways to your desktop folder:

as a text file

save the drawing

Save a link to a web page

The results of this step should be stored in the folder with your Surname in the My Documents folder.

IV. Grading. Discussion of the results of the work

List the websites you have visited. Please describe these sites. What services do they provide to the user?

At this stage, grades are given based on the results of completing tasks 1 and 2.

V. Reflection.

Today we “walked” around the Internet, got acquainted with the concept of a network - WWW, searched for information on various queries, learned how to correctly receive information from the Internet, got acquainted with such concepts as a browser, URL address, search engines

What did you like about the lesson? What didn't you like?
What was new for you in the lesson?

VI. Homework.

Find information on the Internet about the number of users of the most common search engines. When and how did @ originate?

Millions of sites are hosted on the web, and many outdated resources, garbage and unfair advertising are adjacent to relevant information.

The Internet is the most democratic source of information. Everyone can place their own resource on the Web and express their opinion. This is both a strength and a weakness of the World Wide Web.

Finding information on the Internet would probably be very difficult if powerful search tools were not created: search engines(search engines) rating catalogs(rubricators), thematic lists of links, online encyclopedias and dictionaries.

To search for various kinds of information, various tools turn out to be the most effective.

Resource directories

The directory has a hierarchical structure. Thematic sections of the first level define the broadest possible topics, such as "sport", "leisure", "science", "shopping", etc. Each section can have subsections. The user can specify the area of interest to him, traveling through the directory tree and gradually narrowing the search area. For example, when searching for information about laptops, the search chain might look like this: Information Technology -> Computers -> Laptops. Having reached the desired subdirectory, the user finds a set of links in it.

Usually, all links in the directory are profile links, since it is not programs that are involved in compiling catalogs, but people. It's obvious that if you are looking for general information on some broad topic, then it is advisable to refer to the catalog. If you need to find a specific document, then the catalog will be an ineffective search tool.

Often, resource catalogs are also ratings, i.e. The catalog invites the sites registered in it to install on their pages visit counter, and displays lists of links to sites according to their popularity (traffic). The popularity of a resource is evaluated by a number of parameters, including the so-called hosts(number of unique visitors per day) and hits(number of visits to the site per day).

One of the most popular rating catalogs is Rambler's Top 100. (http://top100.rambler.ru/top100/). It is often interesting to assess the state of not all-Russian, but regional resources on a specific topic. To review Krasnoyarsk web resources and the region, you can recommend the catalogs-ratings of resources Krasland (http://www.krasland.ru/) and Stalker (http://www.stalker.internet.ru/).

search engines

Relevant Document- a document whose semantic content corresponds to information request. Modern search engines search by context, i.e. words contained in the query, taking into account the variations of word forms and expanding queries with synonyms. But computers do not understand the meaning, therefore, in the list of responses to a request, along with documents relevant to your request, you can also receive those that do not suit you in any way.

It's obvious that the percentage of received relevant documents depends on the ability to correctly issue a request. The proportion of relevant documents in the list of all found by the search engine is called search accuracy. Irrelevant documents are called noise. If all found documents are relevant (no noise), then the search accuracy is 100%. If all relevant documents are found, then the completeness of the search is 100%.

Thus, the quality of the search is determined by two interdependent parameters: the accuracy and completeness of the search. Increasing the completeness of the search reduces the accuracy, and vice versa.

Search engines can be compared to a help desk, whose agents go around businesses collecting information into a database. When contacting the service, information is issued from this database. The data in the database becomes outdated, so agents update it periodically. In other words, the help desk has two functions: 1) creating and constantly updating data in the database and 2) searching for information in the database at the request of the client.

Similarly, a search engine consists of two parts: the so-called search robot(or spider) that traverses the Web servers and builds a database, and search engine links relevant to the user's query in the database.

It should be noted that, when processing a specific user request, the search engine operates with an internal database (and does not start traveling on the Web). Although the search engine database is constantly updated, the search engine cannot index all Web documents: there are too many of them. The problem of insufficient search completeness is not only the limited internal resources of the search engine, but also the fact that the speed of the robot is limited, and the number of new Web documents is constantly growing.

The most popular search engines today are Google (www.google.com, www.google.ru) and Yandex (www.yandex.ru).

Online encyclopedias and reference books

In some cases, it may be necessary to find not just a document containing a keyword, but the interpretation of a certain word. When searching for an unfamiliar term using a search engine, you run the risk of getting a whole series of articles in which this term is used, and at the same time not knowing what it really stands for. Such a search is preferably carried out in an online encyclopedia.

One of the largest online encyclopedias is the Yandex. Encyclopedia resource (http://encycl.yandex.ru/) - this project contains 14 encyclopedias, including articles from the Great Soviet Encyclopedia and the Brockhaus and Efron Encyclopedia. The "Encyclopedia of Cyril and Methodius" (http://www.km.ru) also belongs to the large ones.

In addition to the transfer of traditional dictionaries to the hypertext environment, encyclopedic wiki projects are rapidly developing. Wiki is a website for collecting and structuring written information. It is characterized by the fact that all visitors can fill in and edit the information posted on it. http://ru.wikipedia.org/ - Wikipedia in Russian - part of a multilingual project, the purpose of which is to create a complete encyclopedia in all languages of the Earth.

History of the World Wide Web

The inventors of the World Wide Web are Sir Timothy John Berners-Lee(b. June 8, 1955) and, to a lesser extent, Robert Cayo. Tim Berners-Lee is a technology author HTTP, URI/URL and HTML. In 1980 he worked for the European Council for Nuclear Research (French: Conseil Européen pour la Recherche Nucléaire, CERN) as a software consultant. It was there, in Geneva (Switzerland), that he wrote the Enquire program for his own needs, which laid the conceptual foundation for the World Wide Web.

AT 1989 While working at CERN on the organization's intranet, Tim Berners-Lee proposed the global hypertext project now known as the World Wide Web.

As part of the project, Berners-Lee wrote the world's first web server and the world's first hypertext web browser, called "WorldWideWeb".

Berners-Lee created the world's first website at http://info.cern.ch/, the site is now archived. This site is online August 6, 1991. This site described what the World Wide Web is, how to install a web server, how to use a browser. This site was also the world's first Internet directory because Tim Berners-Lee later hosted and maintained a list of links to other sites there.

Yet the theoretical foundations of the web were laid much earlier. Back in 1945, Vanniver Bush developed the concept of "Memex" - auxiliary means of "expanding human memory." Memex is a device in which a person stores all his books and records (and ideally, all his knowledge that can be formally described) and which gives out the necessary information with sufficient speed and flexibility. Bush also predicted a comprehensive indexing of texts and multimedia resources with the ability to quickly find the necessary information. The next significant step towards the World Wide Web was the creation of hypertext (a term coined by Ted Nelson in 1965).

Rice. 75. Logo of the World Wide Web Consortium

Since 1994, the main work on the development of the World Wide Web has taken over World Wide Web Consortium, founded and still led by Tim Berners-Lee. W3C is an organization that develops and implements technology standards for the Internet and the World Wide Web.

Development prospects

The current concept of the development of the World Wide Web today is the creation of a semantic (meaningful) web. The author of the concept of the semantic web is also Tim Berners-Lee. Semantic web (semantic web)- this is an add-on over the existing World Wide Web, which is designed to make the information posted on the network more convenient. understandable for computers.

Currently, computers take a rather limited part in the formation and processing of information on the Internet. The functions of computers are mainly reduced to the storage, display and retrieval of information. At the same time, the creation of information, its evaluation, classification and updating - all this is still performed by a person. How to include the computer in these processes? If a computer cannot yet be taught to understand human language, then a language that the computer can understand must be used. That is, ideally, all information on the Internet should be placed in two languages: in a human language for a person and in a computer language for understanding a computer. The Semantic Web is the concept of a network in which each resource in human language would be provided with a description understandable to a computer.

Programs will be able to find the necessary resources themselves, process information, classify data, identify logical relationships, draw conclusions and make decisions based on these conclusions. If widely adopted and implemented well, the Semantic Web has the potential to revolutionize the Internet.

The seminal work on the Semantic Web is Spinning the Semantic Web: Unleashing the Full Potential of the World Wide Web by Berners-Lee in 2005.

Tasks

1. The first global computer network was named:

bitnet;
ARPANet;
NSFNet.

2. Internet provider is:

Internet Service Provider Organization;
organization engaged in the creation of web-sites;
peripheral device used to communicate with another computer.

3. FTP is:

mail client;
IP-telephony program;
file transfer protocol.

4. The web page URL is set: http://www.sgzt.com/sgzt/archive/content/2005/03/043. What is the name of the protocol for accessing this information resource?

sgzt/archive/content/2005/03/043;
http;
www.sgzt.com.

5. In which of the following first-level domain zones can a legal entity registered in the Russian Federation acquire a domain name?

.com;
in both.

6. Among the given entries, specify the correct IP address of the computer:

198.15.19.216;
298.15.19.216;
200,6,201,13;
http://www.ipc.ru;
www.ip-address.com.

7. Which of the given e-mail addresses is correct?

8. What is HTML?

One of the protocols of the TCP/IP family;
Document hypertext markup language;
Programming language.

Similar information.

Millions of sites are hosted on the web, and many outdated resources, garbage and unfair advertising are adjacent to relevant information.

The Internet is the most democratic source of information. Everyone can place their own resource on the Web and express their opinion. This is both a strength and a weakness of the World Wide Web.

To search for various kinds of information, various tools turn out to be the most effective.

Resource directories

search engines

The most popular search engines today are Google (www.google.com, www.google.ru) and Yandex (www.yandex.ru).

Online encyclopedias and reference books

In addition to the transfer of traditional dictionaries to the hypertext environment, encyclopedic wiki projects are rapidly developing. Wiki- a website for collecting and structuring written information. It is characterized by the fact that all visitors can fill in and edit the information posted on it. http://ru.wikipedia.org/ - Wikipedia in Russian - part of a multilingual project, the purpose of which is to create a complete encyclopedia in all languages of the Earth.

THE MOST IMPORTANT

Free access to information, regardless of borders and distances, has become possible thanks to the World Wide Weh (WWW, Web, World Wide Web) - a worldwide information repository that exists on the technical basis of the Internet.

To move the user on the "web" help special

programs called browsers. The search for the desired document in WW&V can be performed: by specifying the address of the document; by moving along the web of hyperlinks; through the use of search engines.

There are many search engines. Most of them have three main types of search: for any of the words; in all words; exactly on the phrase.

Questions and tasks

1. Perform a literal translation of the phrase 4 YWorld Wide Web.

2. Describe the organization of the WWW in general terms.

4. Imagine that the text of this paragraph is posted on Web-cafrre. What words from the text can be chosen as key words in order to most accurately convey its meaning? List up to 10 such words.

5. Do you know the address of your school's website? What sites would you recommend visiting your classmates?

b. What browser do you use at school?

7. What search engines do you know?

8. List the main types of search queries.

9. Find information on the World Wide Web about the number of users of the most common search engines.

Present the results of these queries graphically using Euler circles. Specify query designations in ascending order of the number of documents that the search engine will find for each query.

11. Search the World Wide Web for answers to the following questions.

Who is Norbert Wiener and what is his role in the study of information processes?

Who is Claude Shannon and why is he famous?

By whom and when was the term "hypertext" coined?

Who is considered the inventor of WYVW and when did it happen?

Who is Euler, after whom is the graphic diagram illustrating the relationships between sets named?

Test tasks for self-control

1. Which of the following statements most accurately reveals the meaning of the concept of "information" from an everyday point of view?

a) a sequence of characters of some alphabet

b) the book fund of the library

c) information about the surrounding world and the processes taking place in it, perceived by a person directly or with the help of special devices

d) information contained in scientific theories

2. Continuous called signal:

c) carrying text information

d) carrying any information Z. A signal is called discrete:

a) taking a finite number of definite values

b) continuously changing in time

c) which can be decoded

d) carrying some information aci Yu

4. Information that does not depend on personal opinion or judgment is called:

a) understandable

b) up to date

B) objective

d) useful

5. Information that is significant and important at the moment is called:

a) useful

b) up to date

c) reliable

d) objective

b. According to the way of perception by a person, the following types of information are distinguished:

a) textual, numerical, graphical, tabular, etc.

b) scientific, social, political, economic, religious, etc.

c) ordinary, production, technical, managerial

7. It is known that a physically healthy person receives the largest amount of information with the help of:

a) organs of hearing

b) organs of vision

c) organs of touch

d) olfactory organs

e) taste buds

8. Specify the "extra" object in terms of agreement on the meaning of the signs used:

b) road signs

d) musical signs

9. Specify the "extra" object in terms of the type of writing:

a) Russian

b) English

c) Chinese

d) French

10. Formal languages include:

a) Russian

b) Latin

c) Chinese

d) French

11. According to the form of presentation, information can be conditionally divided into the following types:

a) mathematical, biological, medical, psychological, etc.

b) sign and figurative

c) everyday, scientific, industrial, managerial

d) visual, auditory, tactile, olfactory, gustatory

12. Discretization of information is:

a) a physical process that changes over time

b) quantitative characteristic of the signal

c) the process of converting information from a continuous form to a discrete one d) the process of converting information from a discrete form to a continuous one

13. Give the most complete answer.

Determine which set of letters is encoded by the binary string 0110100011000.

a) EBCEA b) BDDEA c) CG) CEA d) EBAEA

16. The chessboard consists of 8 columns and 8 rows. What is the minimum number of bits required to encode the coordinates of one chess field?

17. In which line are the units of measurement of information arranged in ascending order?

a) gigabyte, megabyte, kilobyte, byte, bit

b) bit, byte, megabyte, kilobyte, gigabyte

c) byte, bit, kilobyte, megabyte, gigabyte

d) bit, byte, kilobyte, megabyte, gigabyte

18. The size of the message is 11 KB. The message contains 11,264 characters. What is the power of the alphabet with which the message is written?

a) 64 b) 128 c) 256 d) 512

19. Given a text of 600 characters. It is known that the characters are taken from a table of size 16 x 32. Determine the information volume of the text in bits.

A) 1000 b) 2400 c) 3600 d) 5400

20.
The two texts contain the same number of characters. The first text is made up of alphabetic characters with a capacity of 16, and the second text is made up of alphabetic characters with a capacity of 256. How many times more information is there in the second text than in the first one?

a) 12 b) 2 c) 24

21. Information processes are:

a) the processes of construction of buildings and structures

b) processes of chemical and mechanical water purification

c) the processes of collecting, storing, processing, searching and transmitting information

d) electricity generation processes

22. Under the information carrier it is customary to mean:

a) communication line

b) the Internet

c) computer

d) a material object on which information can be fixed in one way or another

23. Which line correctly represents the information transfer scheme?

a) source encoder - "decoder -" receiver

b) source - "encoder -" communication channel - "decoder -" receiver

c) source encoder interference - "decoder receiver

d) source decoder communication channel -» encoder receiver

24. Hypertext is:

a) very large text

b) text that can be followed by links

c) text typed on a computer

d) text that uses a large font size

25. A search engine is NOT:

d) Yandex

26. The table shows queries to the search engine. Which query will find the most matching pages for it?

a)	breeding & keeping & swordtails & catfish
b)	content & swordsmen
in)	(content & swordsmen) catfish
G)	content & swordtails & catfish

COMPUTER AS A UNIVERSAL DEVICE FOR WORKING WITH INFORMATION

Information retrieval toolsWWW. Useful World Wide Web Addresses Most Common Search Engines on the World Wide Web

Top Related Articles