The World Wide Web was created in. Internet - The World Wide Web is a unity of information resources. Internet services
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The history of the creation and development of the Internet.
The Internet owes its origins to the US Department of Defense and its secret research conducted in 1969 to test methods for allowing computer networks to survive military operations through dynamic message rerouting. The first such network was ARPAnet, which connected three networks in California with a network in Utah using a set of rules called the Internet Protocol (IP).
In 1972, access was opened to universities and research organizations, with the result that the network began to unite 50 universities and research organizations that had contracts with the US Department of Defense.
In 1973, the network expanded to an international scale, uniting networks located in England and Norway. A decade later, IP has been extended with a suite of communication protocols that support both local and wide area networks. This is how TCP / IP was born. Shortly thereafter, the National Science Foundation (NSF) opened NSFnet with the goal of linking 5 supercomputer centers. Concurrent with the introduction of TCP / IP, the new network soon replaced ARPAnet as the backbone of the Internet.
Well, how did the Internet become so popular and developed, and the impetus for this, as well as for turning it into an environment for doing business, was given by the emergence of World Wide web (World Wide Web, WWW, 3W, ve-ve-ve, three doubles) - hypertext systems that made surfing the Internet fast and intuitive.
But the idea of \u200b\u200blinking documents through hypertext was first proposed and promoted by Ted Nelson in the 1960s, however, the level of computer technology existing at that time did not allow it to be implemented, although who knows how it would have ended if this idea has found application ?!
The foundations of what we mean by the WWW today were laid in the 1980s by Tim Berners-Lee during work on the creation of a hypertext system at the European Laboratary for Particle Physics, European Center for Nuclear Research ).
As a result of these works, in 1990 the scientific community was presented with the first text browser (browser), which allows viewing text files linked by hyperlinks on-line. This browser was made available to the general public in 1991, but its adoption outside academia has been slow.
A new historical stage in the development of the Internet is due to the release of the first Unix version of the Mosaic graphical browser in 1993, developed in 1992 by Marc Andreessen, an internship student at the National Center for Supercomputing Applications (NCSA), USA.
Since 1994, after the release of the Mosaic browser versions for Windows and Macintosh operating systems, and soon after that - the Netscape Navigator and Microsoft Internet Explorer browsers, the explosive spread of the popularity of the WWW, and as a consequence of the Internet, began among the general public, first in the United States, and then and around the world.
In 1995, the NSF transferred responsibility for the Internet to the private sector, and since then the Internet has existed as we know it today.
Internet services.
Services (services) are types of services that are provided by servers on the Internet.
In the history of the Internet, there were different types of services, some of which are no longer used, others are gradually losing their popularity, while others are flourishing.
Let's list those of the services that have not lost their relevance at the moment:
-World Wide Web - World Wide Web - a service for searching and viewing hypertext documents, including graphics, sound and video. -E-mail - email - transfer service electronic messages.
-Usenet, News - newsgroups, newsgroups - a kind of online newspaper or bulletin board.
-FTP - file transfer service.
-ICQ is a service for real-time communication using the keyboard.
-Telnet - service of remote access to computers.
-Gopher - service for accessing information using hierarchical catalogs.
Among these services, one can distinguish services designed for communication, that is, for communication, transfer of information (E-mail, ICQ), as well as services whose purpose is to store information and provide access to this information for users.
Among the latter services, the leading place in terms of the amount of stored information is occupied by the WWW service, since this service is the most convenient for users and the most advanced in technical terms. The second place is taken by the FTP service, since no matter what interfaces and conveniences are developed for the user, information is still stored in files that this service provides access to. Gopher and Telnet services can now be considered "dying out", since new information almost does not come to the servers of these services and the number of such servers and their audience is practically not increasing.
World Wide Web - the world wide web
World Wide Web (WWW) - hypertext, or rather, hypermedia information system search for Internet resources and access to them.
Hypertext - information structure, which allows you to establish semantic connections between elements of text on a computer screen so that you can easily make transitions from one element to another.
In practice, in hypertext, some words are highlighted by underlining or coloring in a different color. Highlighting a word indicates that there is a connection between this word and some document, in which the topic associated with the highlighted word is considered in more detail.
Hypermedia is what you get if you replace the word "text" with "any kind of information" in the definition of hypertext: sound, graphics, video.
Such hypermedia links are possible, since along with text information, you can link any other binary information, for example, encoded sound or graphics, So, if the program displays a map of the world and if the user selects any continent on this map with the mouse, the program can here give graphic, sound and text information about it.
The WWW system is built on a special data transfer protocol called the HTTP Hypertext Transfer Protocol (read "h-t-t-pi", HyperText Transfer Protocol).
The entire content of the WWW system consists of WWW pages.
WWW-pages - hypermedia documents of the World Wide Web system. They are created using the hypertext markup language (HTML). One WWW page is actually a set of hypermedia documents located on the same server, interlaced with mutual links and related by meaning (for example, containing information about one educational institution or one museum). Each page document, in turn, can contain multiple on-screen pages of text and illustrations. Each WWW-page has its own "homepage" - a hypermedia document containing links to the main components of the page. Cover page addresses are distributed on the Internet as page addresses.
A collection of web pages linked together by links and designed to achieve a single purpose is called a web site.
Email.
Email appeared about 30 years ago. Today it is the most massive means of information exchange on the Internet. The ability to receive and send e-mail can be useful not only for communicating with friends from other cities and countries, but also in a business career. For example, when applying for a job, you can quickly send your resume via e-mail to various companies. In addition, many sites where you need to register (on-line games, online stores, etc.) often require you to specify your e-mail. In short, e-mail is a very useful and convenient thing.
E-mail (Electronic mail, English mail - mail, abbreviated e-mail) serves to transfer text messages within the Internet, as well as between other e-mail networks. (Picture 1.)Using e-mail, you can send messages, receive them in your e-mail box, respond to correspondent letters, send copies of letters to several recipients at once, forward the received letter to another address, use logical names instead of addresses, create several subsections mailbox for all kinds of correspondence, include various sound and graphic filesas well as binaries - programs.
To use E-mail, the computer must be connected to telephone network via modem.
A computer connected to the network is considered a potential sender and receiver of packets. Each host on the Internet, when sending a message to another host, splits it into fixed-length packets, typically 1500 bytes. Each packet is supplied with the recipient's address and the sender's address. Packets prepared in this way are forwarded through communication channels to other nodes. When receiving any packet, the host analyzes the recipient's address and, if it matches its own address, the packet is accepted, otherwise it is sent on. Received packets belonging to the same message are accumulated. Once all packets of one message are received, they are concatenated and delivered to the recipient. Copies of packets are stored on the sender nodes until a response is received from the recipient node about the successful delivery of the message. This ensures reliability. To deliver a letter, the addressee only needs to know his address and the coordinates of the nearest mailbox. On the way to the addressee, the letter passes several post offices (nodes).
FTP service
Internet service FTP (file transfer protocol) stands for protocol
file transfer, but when considering FTP as an Internet service, there is
not just a protocol, but a service - access to files in file
archives.
IN UNIX systems FTP - standard programoperating on the TCP protocol,
always supplied with the operating system. Its original purpose is
transfer of files between different computers running on TCP / IP networks: to
one of the computers runs a server program, on the second the user runs
a client program that connects to the server and sends or receives over
FTP files. (Figure 2)
Figure 2. FTP protocol diagram
FTP is optimized for file transfers. Therefore, FTP programs have become
part of a separate Internet service. The FTP server can be configured like this
in a way that you can connect to it not only under a specific name, but also under
by the conventional name anonymous - anonymous. Then not all of the
the computer's file system, but a set of files on the server that
composes the contents of the anonymous ftp server - a public file archive.
Today public file archives are organized mainly like servers.
anonymous ftp. A huge amount of information is available on such servers today.
and software. Pretty much everything that can be provided
to the public as files, available from anonymous ftp servers. These are programs -
freely distributed and demos and multimedia, this is finally
just texts - laws, books, articles, reports.
Despite its prevalence, FTP has many disadvantages. Programs-
FTP clients may not always be user-friendly or easy to use. Not always possible
understand what kind of file is in front of you - whether it is the file that you are looking for, or not. No
a simple and versatile search engine on anonymous ftp servers - although for
this is what special programs and services exist, but they do not always give
desired results.
FTP servers can also organize access to files under a password - for example,
to their clients.
TELNET service
The purpose of the TELNET protocol is to provide a fairly general, bi-directional, eight-bit byte-oriented communication facility. Its main purpose is to allow terminal devices and terminal processes to communicate with each other. It is contemplated that this protocol can be used for terminal-to-terminal communication ("binding") or for process-to-process communication ("distributed computing").
Figure 3. Telnet terminal window
Although Telnet sessions distinguish between client and server sides, the protocol is actually completely symmetric. Once the transport connection (usually TCP) is established, both ends play the role of "network virtual terminals" (eng. Network virtual terminal, NVT) exchanging two types of data:
Application data (that is, data that goes from the user to the server-side text application and back);
Telnet protocol commands, a special case of which are options that serve to understand the capabilities and preferences of the parties (Figure 3).
Although a Telnet session running over TCP is inherent in full duplex, the NVT should be considered a half duplex device, operating in buffered string mode by default.
The application data passes through the protocol without changes, that is, at the output of the second virtual terminal, we see exactly what was entered at the input of the first. From the point of view of the protocol, data is simply a sequence of bytes (octets), by default belonging to the ASCII set, but with the option Binary - any. Although extensions have been proposed to identify a character set, they are not used in practice.
All application data octet values \u200b\u200bexcept \\ 377 (decimal: 255) are transported as is. Octet \\ 377 is transmitted in sequence \\ 377 \\ 377 of two octets. This is because the \\ 377 octet is used in the transport layer to encode options.
The protocol provides minimal functionality by default and a set of options that extend it. The concept of negotiated options requires negotiation when each option is enabled. One party initiates a request and the other party can either accept or reject the offer. If the request is accepted, then the option takes effect immediately. The options are described separately from the protocol itself, and their support by the software is optional. The protocol client (network terminal) is instructed to reject requests to enable unsupported and unknown options.
Historically Telnet has served remote access to the interface command line operating systems. Subsequently, it was used for other text-based interfaces, up to MUD games. In theory, even both sides of a protocol can be not only humans, but programs as well.
Sometimes telnet clients are used to access other protocols based on TCP transport, see Telnet and Other Protocols.
The telnet protocol is used in the FTP control connection, that is, logging into the server with the telnet ftp.example.net ftp command to perform debugging and experimentation is not only possible, but also correct (as opposed to using telnet clients to access HTTP, IRC and most other protocols ).
The protocol does not provide for the use of either encryption or data authentication. Therefore, it is vulnerable to any kind of attack to which its transport is vulnerable, that is, the TCP protocol. For the functionality of remote access to the system, the SSH network protocol is currently used (especially its version 2), during the creation of which the emphasis was placed on security issues. So it should be borne in mind that a Telnet session is quite defenseless, unless it is carried out on a fully monitored network or using security on network layer (various implementations of virtual private networks). Due to the unreliability of Telnet as a management tool operating systems refused long ago.
What is the World Wide Web?
A web, or "web", is a collection of linked pages of specific information. Each such page can contain text, images, video, audio and other various objects. But apart from this, there are so-called hyperlinks on the web pages. Each such link points to another page, which is located on some other computer on the Internet.
Various information resources, which are interconnected by means of telecommunications and are based on hypertext representation of data, form the World Wide Web (WWW).
Hyperlinks link pages that are located on different computerslocated in different parts of the globe. A huge number of computers, which are united in one network, is the Internet, and the "World Wide Web" is a huge number of web pages located on computers of the network.
Every web page on the Internet has an address - URL (English Uniform Resource Locator - unique address, name). It is at the address that you can find any page.
How was the World Wide Web created?
On March 12, 1989, Tim Berners-Lee presented to the CERN leadership a project of a unified system for organizing, storing and sharing information, which was supposed to solve the problem of exchanging knowledge and experience between the Center staff. Berners-Lee proposed to solve the problem of access to information on different computers of the employees with the help of browser programs that provide access to the computer-server where the hypertext information is stored. After the successful implementation of the project, Berners-Lee was able to convince the rest of the world to use uniform standards for Internet communication, using the standards of the hypertext transfer protocols (HTTP) and the universal markup language (HTML).
It should be noted that Tim Berners-Lee was not the first creator of the Internet. The first system of protocols for transferring data between networked computers was developed by employees of the US Defense Advanced Research Projects Agency (DARPA) Vinton Cerf and Robert Kahnin the late 60s - early 70s of the last century. Berners-Lee only suggested using the capabilities of computer networks to create new system organization of information and access to it.
What was the prototype of the World Wide Web?
Back in the 60s of the XX century, the US Department of Defense set the task of developing reliable system transmission of information in case of war. The United States Advanced Research Projects Agency (ARPA) has proposed developing a computer network for this. It was named ARPANET (Advanced Research Projects Agency Network). The project brought together four academic institutions - the University of Los Angeles, the Stanford Research Institute, and the Universities of Santa Barbara and Utah. All work was funded by the US Department of Defense.
First data transfer over computer network took place in 1969. A Los Angeles University professor with his students tried to enter a Stanford computer and send the word "login". Only the first two letters L and O were successfully transmitted. When they typed the letter G, the communication system failed, but the Internet revolution took place.
By 1971, a network with 23 users had been established in the United States. The first program for sending e-mail over the network was developed. And in 1973, University College London and Government Services in Norway joined the network and the network became international. In 1977, the number of Internet users reached 100, in 1984 - 1,000, in 1986 there were already more than 5,000, in 1989 - more than 100,000. In 1991, the World-Wide Web (WWW) project was implemented at CERN. In 1997, there were already 19.5 million Internet users.
Some sources indicate the date of the appearance of the World Wide Web a day later - March 13, 1989.
World Wide Web (WWW)
The World Wide Web (WWW) is the most popular and interesting service on the Internet, a popular and convenient means of working with information. The most common name for a computer on the Internet today is www, more than half of the Internet's data traffic comes from WWW. The number of WWW servers today cannot be estimated accurately, but according to some estimates there are more than 30 million. The growth rate of WWW is even higher than that of the Internet itself.
WWW is a worldwide repository of information in which information objects are linked by a hypertext structure. Hypertext is primarily a system of documents with cross-references, a way of presenting information using links between documents. Since the WWW system makes it possible to include in these documents not only texts, but also graphics, sound and video, the hypertext document has become a hypermedia document.
A bit of WWW history. The World Wide Web (WWW) is one of the most important components worldwide network... And she has her own story.
It is interesting. Switzerland is home to the European Laboratory for the Study of Physical Particles (CERN). In 1980, a man named Tim Bernes-Lee, then working at CERN, began developing a project for a global computer network that would provide physicists around the world with access to various information. It took nine years. In 1989, after many years of technical experimentation, Mr. Tim proposed a specific option, which was the beginning of the World Wide Web, or WWW for short.
Over time, many realized that such services could be used by different people, not just physicists. The WWW grew rapidly. Many people helped her with this: some developed hardware, others created software that developed the WWW, and others improved communication lines. All this allowed her to become what she is now - the "World Wide Web".
Principles of client and server operation. WWW works on the principle of client-server, more precisely, client-servers: there are many servers that, upon the client's request, return a hypermedia document - a document consisting of parts with a variety of information representations (text, sound, graphics, three-dimensional objects, etc.) ), in which each element can be a link to another document or part of it. Links in WWW documents are organized in such a way that each information resource in global network The Internet is unambiguously addressable, and the document you are reading at the moment is capable of linking both to other documents on the same server and to documents (and in general to Internet resources) on other computers on the Internet. Moreover, the user does not notice this and works with the entire information space of the Internet as a single whole.
WWW links point not only to documents specific to the WWW itself, but also to other services and information resources of the Internet. Moreover, most WWW client programs (browsers, navigators) not only understand such links, but are also client programs for the corresponding services: FTP, gopher, Usenet news, e-mail, etc. In this way, software WWW are universal for various services The Internet, and the WWW information system itself plays an integrating role.
Let's list some of the terms used in the WWW.
The first term - html - is a set of control sequences of commands contained in an html document and defining the actions that the viewer (browser) must perform when loading this document. This means that each page is a regular text file containing text that is visible to everyone, and some instructions for the program, invisible to people in the form of links to other pages, images, servers. Thus, questionnaires, registration cards are filled in, sociological surveys are conducted.
The second term is URL (uniform resource locator). This is the name of the very links to information resources of the Internet.
Another term is http (hypertext transfer protocol). This is the name of the protocol over which the WWW client and server communicate.
WWW is a direct access service that requires a full-fledged Internet connection and, moreover, often requires fast communication lines if the documents you are reading contain a lot of graphics or other non-textual information.
The rapid development of the Internet, which began in the early 90s, is largely due to the emergence new technology WWW. This technology is based on the hypertext technology, which is widespread on all computers connected to the Internet.
When using hypertext technology, the text is structured and words-links are highlighted in it. When the link is activated (for example, using the mouse), the transition to the text fragment specified in the link or to another document occurs. So, we could transform our text into hypertext by highlighting the words "hypertext technology" in the first paragraph and fixing that when this link is activated, there will be a transition to the beginning of the second paragraph.
WWW technology allows you to navigate not only within the original document, but also to any document located on this computer and, most importantly, to any document on any computer that is currently connected to the Internet. Documents implemented using WWW technology are called Web pages.
The structuring of documents and the creation of Web pages is carried out using the HTML (Hyper Text Markup Language) language. Text editor Word allows you to save documents as Web pages. Web browsing is done using special programs browsers view. Currently the most common browsers are Internet Explorer, Netscape Navigator, Opera.
If your computer is connected to the Internet, you can download one of the browsers and go on a trip on the World Wide Web. First, you need to download a Web page from one of the Internet servers, then find the link and activate it. This will load a Web page from another Internet server, which may be located in a different part of the world. In turn, you can activate the link on the given Web page, the next Web page will load, and so on.
The Internet is growing at a very fast pace, and it is becoming increasingly difficult to find the information you need among tens of millions of documents. To find information, special search engines are used, which contain accurate and constantly updated information about the content of tens of millions of Web pages.
Scientific and technological progress does not stand still, but is in constant development, search, improvement. Perhaps the most useful invention of the human genius, the Internet, was invented relatively recently, by the standards of the development of civilization. At its core, it is a unique data exchange tool.
Internet (Network, Internet) - virtual environment, guaranteeing access to information resources, the elements of which are personal computers. They are combined into a single circuit and endowed with unique addressing features, using high-speed communication lines with host computers.
The Internet is a huge network of countless devices. It serves to exchange information that exists in this network in different forms... Nowadays, it's not just computers that can connect to the Internet. Mobile phones, tablets, game consoles, other gadgets and even TVs can easily go online at any time.
The importance of this information space is indisputable also due to the amazing possibilities of communication between users of all devices connected to the Network.
Technically, the online space is formed by countless computer devices connected to each other. Billions of PC users living in different countries, communicate with each other every day, transmit and receive useful information, download arrays of digital data in the form of applications, programs, utilities; watching videos, listening to music.
The online environment has another important property - the unlimited possibilities for storing information. Personal experience is transmitted via the Internet, in addition, it is a unique platform for informing the masses for modern media and a colossal repository of world knowledge.
What is the Internet?
In order for PC owners living on different continents to freely use the services of searching for network resources, trunk cables are laid at the bottom of the ocean through which useful information is pumped around the clock.
The personal computer is controlled by special protocols. This is a kind of instruction that allows you to set the rules for communication between devices. The single criterion for building a software protocol is the IP address. Thanks to this structure, any participant receives his own digital address, with the help of which the search and identification takes place.
For example, after entering the name “novichkam.info” into the browser line, in a matter of moments, the client is on a web site that offers help to beginners. Technically, a software robot simply finds the IP address code that is assigned to a particular site.
The machine algorithm includes the following operations:
- the request is recorded by the main server, where the name of the required thematic data array is stored;
- the name of this resource is found in memory, i.e. finding the required IP address;
- the client goes to the website.
There are other protocols as well, such as HTTP. Requests in a different way are made with the addition of a prefix http: //
What is the World Wide Web (WWW)
For most of the target audience, it is of great interest to define an Internet service as the World Wide Web in abbreviated form (WWW or simply WEB). Its definition refers to a set of interconnected web pages, access to which is provided by a limited number of PCs connected to the Network.
A set of text files, marked up in HTML with links to links, posted on an electronic site, was named a website. You can get acquainted with the content of this or that website by activating the browser to search for the address name.
The web is today positioned as the most demanded and popular service in the online space, i.e. the Internet. Hypertext links are an important element of the WEB. By clicking on the link of the required document or by requesting a unique URL (name code, path) in the browser, a person can view the required array of text.
Addressing system
When you enter an incorrect address name into the search bar or click on a broken link, the browser will promptly signal an error (confirm the absence desired page). Often, upon request, a person gets access to an advertising (fraudulent) site.
In this situation, you should correct the inaccuracy in the query string field without trying to examine the advertising website for security reasons. The fact is that these sites can be infected with a virus. If the resource was created for the purpose of fraud, then it would be useful to familiarize yourself with our section, where the most popular methods of fraud on the network are perfectly described.
The main thing in the address of any site is the domain, which serves for ease of memorization. The domain usually displays the address home page... At the same time, it should be understood that for the technical download of the page, the computer device uses IP with the protocol “12.123.45.5” ... Agree, this combination is much more difficult to remember than domain name our site.
It is important to know that entering “http: //” or the prefix “WWW” in the search bar is NOT required at all. Better to use services search engine, where the mistake will be immediately corrected, and domain entry is possible without the confusing zone.
What does the Internet give us?
- unlimited communication and communication
Many are looking for like-minded people here, communicating on popular social projects and forums. Others like the unique personal communication service via ICQ or Skype. Visitors to the dating website expect to find their other half here;
- endless possibilities of entertainment and organization of personal leisure
Here you can listen to popular music tracks for free, enjoy the latest filmography of film studios, play various games, including gambling, get acquainted with the works of modern authors and classics of the literary genre, take polls, tests, etc.
- self-education
In the mass communication environment, you can not only read useful articles, but also participate in trainings, master classes, watch video lessons;
- creative personality development
Here you can meet rare people, visit their professional projects for creative and personal improvement;
- purchase of goods and services
Clients of virtual supermarkets can buy goods without leaving their homes. Online you can buy shares of industrial companies, order tickets, book a hotel room, etc .;
- new ways of earning
There are more types of earnings on the Internet. For example, you can open an online store by creating your own blog (website). For those who are just trying their hand at this field, it is easier to start with freelancing: write articles on order, sell photos, offer services for the creation and promotion of various projects, do web design and programming.
- much more. The information on our website will help you find out not only all the possibilities of this global network, but also perfectly, being in it.
