Hypertext - what is it in computer science? Who introduced the term "hypertext"? By whom and in what year the term hypertext was introduced Hypertext message.

In the 80s of the last century, the term "hypertext" in a philological sense, the famous structuralist-narratologist Gerard Genette used it in his book "Palimpsests", discussing various types of intertextual connections. Gerard Gennet developed a practical model for the study of intertextual relations, focusing not on private textual relationships, but on the work as a whole structure. He proposed his own classification of different types of text interaction. However, the term "hypertext" within the Genette concept had a narrower meaning than in computer development, where it becomes a key word.

There are many definitions of hypertext. The simplest one can be found in almost any web design guide:

Hypertext is text linked by links to other texts.

Ted Nelson defined hypertext as follows:

“By hypertext, I don't mean non-sequential writing, but text that branches out and allows the reader to choose<…>... Simply put, it is a series of text chunks connected by links that offer the reader different paths. "

V. Rudnev's dictionary of XX century culture gives the following definition of hypertext:

Hypertext- a text arranged in such a way that it turns into a system, a hierarchy of texts, at the same time constituting a unity and a multitude of texts.

For the sake of completeness, we will present other fairly typical definitions of hypertext collected from various sources.

1... Hypertext- this is a combination of the semantic structure, the structure of internal connections of a certain content, and the technical environment, technical means that enable a person to master the structure of semantic connections, to make transitions between interrelated elements.

2. Mechanism, consisting in the ability to connect passages of text, move from one to another, is called hypertext or nonlinear text.

3. Overtext, a certain unit of information, parts of which are texts and / or text, parts of which have "superconnections", that is, they are connected to each other not by a linear relationship in a one-dimensional space (by a sequence relationship as in an ordinary natural language text), but by a variety of different relationships represented by in multidimensional space. In hypertext there are no predetermined restrictions on the nature of the links (network).

4. Hypertext can be defined as non-linear documentation that branches and interconnects, allowing the reader to explore the information it contains in a sequence that he chooses. Hypertext allows text, audio, photographs, blueprints, maps, moving pictures, and other forms of information to be linked into a meaningful whole that can be accessed through an indexing system focused on specific ideas rather than specific words in the text.

5. Hypertext is a text organized in such a way that from some of its elements aleatoric (at the reader's choice) transition to several other elements at once is possible, or links to other elements of the same text or other texts are possible.

6. Hypertext is the presentation of information as a linked network of nodes, in which readers are free to navigate in a non-linear fashion. It allows for the possibility of a plurality of authors, a blurring of the functions of the author and the reader, the expansion of work with fuzzy boundaries and a plurality of ways of reading.

R.Barthes also wrote about almost the same: “... the text is permeated with a network of countless intertwining internal passages that have no power over each other; he is a galaxy of signifiers, not a structure of signifieds; it has no beginning, it is reversible; it can be entered through many entrances, none of which can be considered the main one; the string of codes mobilized by him is lost somewhere in the infinite distance, they are "insoluble" (their meaning is not subject to the principle of decidability, so any decision will be random, like a roll of dice); this purely plural text can be captured by various semantic systems, but their circle is not closed, for the measure of such systems is the infinity of the language itself. "

Hyperlink(English hyperlink) - a part of a hypertext document that refers to another element (command, text, title, note, image) in the document itself, to another object (file, directory, application) located on a local disk or in a computer network, or to the elements of this object.

A hyperlink can be added to any element of a hypertext document and is usually highlighted graphically. In HTML documents, text links are highlighted in blue by default, and when you hover over them in the browser window, they change, for example, change color or are underlined. When navigating in the browser using the keyboard, text and image links are highlighted with a rectangular dotted frame. A previously visited link is usually highlighted in a different color from the unvisited link.

A "broken" link is a hyperlink that refers to an object that is missing for some reason, for example, if a document or file has been deleted or moved by the administrator of the resource on which it was located, or if the resource itself is not available. Usually, in this case, a message with an error code appears on the page, but this does not always happen.

A hyperlink is a fragment of an HTML document and its basic element pointing to another file, which can be located on the Internet, containing the full path (URL) to this file. A hyperlink for a user is a graphic image or text on a website, in an e-mail or in any electronic document that establishes a connection and allows you to go to other objects on the Internet.

To define a link in HTML, the tag is used , the structure of which is of the form Link text, where filename is the name of the file or Internet address to which you want to link, and Link Text is the text of the hypertext link that will be shown directly in the HTML document.

· My works - refers to the document my_work.html, forming a hypertext link in the form of the word "My works";

· My photo album - refers to the file my_photo.html located in the photo directory and forms a link in the form of the text "My photo album";

· - refers to a resource located on a remote server.

Internet addressing

Domain name

IP address- network address of a node in a computer network built using the IP protocol. When communicating via the Internet, the global uniqueness of the address is required; in the case of working in a local network, the uniqueness of the address within the network is required.

Address structure

An IP address has two parts: the network number and the host number. In the case of an isolated network, its address can be selected by the administrator from the address blocks specially reserved for such networks (192.168.0.0/16, 172.16.0.0/12 or 10.0.0.0/8). If the network is to work as an integral part of the Internet, then the network address is issued by the provider or regional Internet registrar. The IP node number is assigned regardless of the local node address. By definition, a router is part of several networks at once. Therefore, each port on the router has its own IP address. An end node can also be part of multiple IP networks. In this case, the computer must have several IP addresses, according to the number of network connections. Thus, the IP address does not characterize a single computer or router, but a single network connection.

Domain name- a symbolic name used to identify areas - units of administrative autonomy on the Internet, or domains - as part of a higher hierarchy of such a area. The common namespace of the Internet operates thanks to the DNS - the domain name system. Domain names make it possible to address Internet sites and network resources located on them (websites, e-mail servers, other services) in a human-friendly form.

A fully qualified domain name consists of the immediate domain name and then the names of all domains to which it belongs, separated by periods. For example, the full name ru.wikipedia.org denotes a third-level domain ru, which is part of the second-level domain of wikipedia, which is part of the top-level domain org, which is part of an unnamed root domain. In everyday speech, a domain name is often understood as a fully qualified domain name.

Hypertext is a term that is used not only in computer science, but also in everyday life, since it is universal for dividing and designating the sources and content of the text.

So, let's try to give a reasonable, accurate and understandable definition of this term.

Hypertext is

Hypertext is text that, using its structure, allows you to move from one text to another. In life, you can find hypertext in any book, encyclopedia, in which there is a reference to other sources.

After reading this or that footnote, a person understands that this information was found in another source and, having opened it, we will be able to read this information in a broader sense.

Hypertext in computer science

The simplest and most accessible example of hypertext in computer science is link. Namely:

web pages;
HTML documents.

In the language of "computer", it is text that contains links. When a person clicks on them, he easily gets to the source or to the site, where the information can be found in its original form.

Hypertext itself can contain not only links to other web pages, but also to graphics, videos or any musical compositions.

So, hypertext is what we encounter every day. In the era of information technology, people, without noticing it, use hypertext every day. But if you think about it, imagine and compare, then really - hypertext and hyperlinks were invented before.

As noted above, links in books are also hypertext. With the advent of computers and other gadgets into our lives, it has become easier to use the Internet than books. All information in one click, following the link, can be found on the World Wide Web.

Hypertext is one of the most important, in my opinion, component in computer science. Thanks to hypertext and hyperlinks, people significantly reduce their time searching for this or that information.

Hypertext is a concept that is constantly found on the Internet, the literature on Internet technologies, as well as What is it and what is it "eaten" with?

The definition says that hypertext is a way of linear or, often, non-linear presentation of information. The use of hypertext technologies facilitates the transition from one block of materials to another.

It is now generally accepted that hypertext is used when working with a computer, mainly on the Internet. Each hyperlink starts with WWW. The term "hypertext" originated in the mid-1960s. It was introduced by the famous American philosopher and sociologist

Its main feature is that hypertext allows users to jump from one page to another, depending on their needs and goals. In this case, the user can always return to the page on which he has already been.

The concept of hypertext is quite interesting in computational linguistics. If we start from high technologies and computers in general, it should be noted that hypertext technologies are encountered at almost every step.

For example, every day you see on which the phone number or address is necessarily indicated. It is believed that this information is hypertext. After all, by calling the number, you sort of "go" to the source of more detailed information. The same can be said about the content in books, magazines. After looking at it, you immediately select the page on which the information you need is located.

It is believed that it was the various reference books, alphabetical indexes, card indexes that were the first hypertext systems.

Today, however, hypertext is mainly associated with computers and the Internet. At the same time, scientists note that it is he who ensures the maximum interaction between humans and computers. It turns out that hypertext is a pretty useful thing.

But what could be hypertext? Just a link? No, hypertext can be labeled in different ways. These can be text links, and digital designations, such as phone numbers, page numbers, and even pictures. It all depends on the information that is presented on the page.

It is also worth saying a few words about hypertext markup. It is artificially created with the help of which they create web pages as well as electronic textbooks. It is thanks to him that the pages are displayed correctly in all Internet browsers.

The first and most popular hypertext markup language is HTML. Invented back in 1990 by Tim Brens-Lee, it is still widely used in the creation of web pages.

Naturally, the HTML language is constantly being improved, new versions are being created, supplemented with new tags and markup rules.

When creating pages, they use both (notepad) and special HTML editors, visual design tools.

So, hypertext is a way of presenting information, which has its own rules, language and patterns. With its help, we can quickly find the information we need and get acquainted with it.

In computer science, hypertext is a concept that denotes text formatted using a markup language and having hyperlinks to other elements in its structure. In a broader sense, hypertext is any text that includes internal references from one part to another.

Hypertext concept

The basic building block of hypertext in computer science is a link. By means of documents and web pages communicate with each other, giving references to the necessary material.

To understand what hypertext is, it's worth looking at a simple example. Suppose a person reads an encyclopedia and on one of the pages sees a term unknown to him, next to which there is a footnote indicating that the meaning of this term is revealed on a certain page. He flips through the book, gets to the desired page and receives the necessary information from there. In informatics, everything happens in the same way, with the exception of greater interactivity - in a web document, some data blocks are formed by links, clicking on which, the reader gets to another page, which reveals in detail the topic of interest.

In addition to text information and links, hypertext can contain graphic elements, video, audio recordings.

Formatting takes place in the hypertext language HTML, with which you can add a link or other interactive element to the text. Accordingly, the text is given a certain structure and ordering.

Prerequisites for the emergence of hypertext

It is necessary to say a few words about the origin of hypertext in computer science. This concept began to emerge at the beginning of the twentieth century, when the American researcher Vannevar Bush developed the idea of a special machine capable of viewing and recording various documents in the form of film microfilms. The innovations in Bush's approach were not in the very principle of such a device, but in the mechanism for accessing information, which was to be implemented precisely by the method of cross-referencing. Accordingly, we can say that he was the first inventor of hypertext as a model of interaction with blocks of information. Links in his system had to be indicated in additional fields of documents, sending the user to the final information.

The emergence of hypertext and the creation of the World Wide Web

However, Bush proposed only a system, and who introduced the term "hypertext"? In 1965, this term first appeared in the publication of the scientist He developed his own system of interaction and text ordering, which he called Xanadu. Nelson's definition of hypertext is:

Hypertext is a form of writing that branches out or is done on demand.

Thus, he became the inventor of hypertext, gave it an appropriate name and a clear definition, based on which people consider hypertext in their usual understanding as a text through which the user can move nonlinearly, following links.

The next step in the development of hypertext was the first conference Hypertext "87 - 99, held in the United States. The ideas presented at this conference interested many scientists.

Two years later, in 1989, Tim Berners-Lee proposes the revolutionary idea of creating the widest hypertext project - WWW (World Wide Web), and a year later, HTML appears, which made it possible to create web pages.

A few words about HTML

It is a hypertext markup language that allows you to format individual elements of a web page to create the necessary structure of the final document. It is not a programming language: in simple terms, HTML with the help of tags indicates to each element of the page in its place and the functionality to be performed.

HTML is interpreted in the browser - on the screen where the site page is displayed, you can see the result of the specified formatting. Previously, HTML was also used for the basic design of sites, but over time, this functionality has almost completely moved to CSS style sheets.

Initially, this language did not have the ability to support multimedia, but only structured a text document. It was conceived as a language that was not supposed to be tied to a specific platform and was intended to be displayed on any output devices, but over time this possibility disappeared, and the emphasis was on wide multimedia functionality instead of cross-platform.

During the entire existence of the HTML markup language, certain standards have been established. HTML version 5 is currently in use. Until 1995, there was no standardization as such, there were many informal and semi-official options. In the fourth version, the standard was globally cleaned of obsolete elements, many tags were abolished, and it became customary to use CSS to style documents.

Hypertext structure

As stated above, hypertext consists of document text containing links. Each link, in turn, consists of two elements:

address part;
pointer.

The address part contains information about where exactly this link redirects, and the pointer is the part of the link displayed to the user, which he follows. To understand what hypertext is, consider an example of how a link is formatted.

It looks like this:

Google

In this example, google.com will be the address that the customer will navigate to when they click on the word Google (it will be highlighted in color, underline, or in some other specified way in the text of the document).

This is a very flexible system, thanks to which you can get to the documents involved in the internal structure of the site, as well as to external resources.

Finally

So, the article discusses what hypertext is in computer science. It is a very widely used system in internet technology. With its help, not only web pages are formatted for ease of use, it is also indispensable in areas such as SEO technologies, when the content of the site is optimized for the work of search engines using the HTML markup language. In addition, it is widely used in multimedia technology and graphics.

The ability to use hypertext is necessary not only in the environment of web developers: it is basic knowledge that will be useful for any confident user to correctly navigate the Internet.

Hypertext very widely used in electronic publications, computer applications and allows you to diversify the presentation information... If you have ever dealt with the graphical user interface of any operating systems then already familiar with hypertext, hypertext is clicked and passed.

The idea of hypertext, like any sensible idea, is simple and consists in giving a person the means to perceive information in the sequence he determines.

Associative thinking is human. We all know how difficult it is to put the thoughts in your head on paper, how much is lost. This is where the costs of our phonetic writing (unlike, for example, Chinese or Japanese), which determines the linear organization information... There are, of course, happy exceptions, for example, a certain character M.E. Saltykov-Shchedrin, having read the document three fingers thick, said: "I cannot understand, but I can answer."

There are many definitions of hypertext and systems that support hypertext, the most common of which are shown in the sidebar.

Let's try to see what is needed to organize work with hypertext using a computer. Hypertext needed to organize relationships between various objects (documents, document fragments or programs). Thus, the first thing we need is the organization of sensitive areas, the activation of which, for example, a mouse click, a keyboard key press, or a word spoken into the microphone, will lead to a transition from one object to another.

Types of hypertext

Sensitive areas can be embedded in objects (this is called internal hypertext) (Figure 2.1.3.1a) or organized into separate objects (this is called external hypertext) (Figure 2.1.3.1b).

Rice. 2.1.3.1 Types of Hypertext

Here are some examples. When a user launches a browser to view documents on the World Wide Web, he is working with hypertext, since its elements (hyperlinks) are embedded in Web pages. When we click on a program or document icon on the Windows desktop, we are using external hypertext, since the programs and documents referenced by the icons "know nothing" about what they are hypertext elements. The transition can be carried out both to the beginning of the document, and to an arbitrary place in it. The examples show that hypertext is easily and naturally used in modern computer technology.

The second thing that is necessary for working with hypertext is hypertext links between objects. These links can be unidirectional (Fig. 2.1.3.1c), bidirectional and multiple, as shown in Fig. 2.1.3.1 g, d.

Hypertext transitions between objects can be unconditional, or they can be carried out only if certain conditions are met, for example, in Fig. 2.1.3.1е presents the so-called loaded connection, which reflects the relationship between objects, in this case, "include". From the above definitions, it can be seen that hypertext is mainly designed to represent information for people, at the same time, the use of loaded links allows the use of hypertext to represent information for processing by computers. So in the above example, you can process a request of the form: "What objects does this object include?" The relationship can be attributed to the strength of the connection, this allows you to limit the neighborhood in which the search is carried out.

Objects and connections form a network. User or computer browsing transitions information called hypertext navigation.

Hypertext systems

Over the past fifty years, a large number of hypertext systems have been developed. We will only consider the implementation of hypertext on the World Wide Web based on the HTML markup language.

Let's take a look at how hypertext is used in HTML, first of all, find out how to specify the addresses of the target objects to which the transition is made. The object address is specified using the so-called Uniform Resource Locator (URL). The Uniform Resource Locator consists of three parts: the protocol, the address of the computer on which the resource is located, and the path in the computer's file system.

The default is HTTP. However, the browser is a multi-purpose tool, so you can use other protocols, for example, transfer files using FTP, access documents in the file system of the local computer.

The protocol name ends with a colon and two slashes, followed by the address of the computer on which the resource is located. This address can be presented either in the form of a domain name, for example, www.mpei.ru, or in the form of a so-called IP-address that uniquely identifies the address of a computer on the Internet, for example, 193.233.70.01. The IP address is a 32-bit binary number with four bytes. Address byte values are represented by four decimal numbers from 0 to 255, separated by periods.

The third part of the address, which locates the object in the server's file system, is separated from the domain name (IP address) of the server with a slash and includes the path to the required object, for example, http://myServer.com/manuals/chapter.html.

The description of hypertext in html is carried out using a special construction tag ... It looks like this:

sensitive area of a hyperlink

Here, the address of the object indicates the uniform resource locator for the object to which the hypertext transition is made, and the sensitive area of the object is the selected text (in the example, the sensitive area of the hyperlink) or an image, clicking on which leads to a hypertext transition to the object.

The transition for the above hyperlinks is made to the beginning of the target document.

If you need to go to a certain fragment within the target document, then you need to define a so-called bookmark in it, for example, .

The transition to the bookmark is carried out by encoding its name, preceded by the # symbol. The transition for the above hyperlinks is carried out to the beginning of the target document. If you want to go to a certain fragment within the target document, then you need to specify a bookmark in it, for example,

sensitive area

As you can see from the above, HTML allows you to implement only unidirectional unloaded hypertext links. Nevertheless, even in this truncated form, hypertext has high functionality and is widely used.

Structure of electronic publications

Unlike traditional editions, for example, books, electronic editions (EI), thanks to hyperlinks, allow you to create a variety of navigation structures, i.e. ways of viewing the edition, based on the basic network structure shown in fig. 2.1.3.1. With the help of hyperlinks, the author of the publication can form any network.

It should be borne in mind that the navigation structure is very important for online electronic publications. The fact is that the online electronic edition is initially a set of separate screen pages. The volume of pages is limited by the logical structure of the publication and the time it is loaded on the user's side. It is believed that the maximum page load time should not exceed 30 seconds, so as not to annoy the user and not distract his attention. A navigational structure is needed to link the individual pages of a publication into a coherent whole, acting as a bindery. The matter is further complicated by the fact that the reader of an electronic edition can start working with it from any of its pages, since the author of the EI cannot control the hyperlinks made to the pages of the EI in other EIs.

Hierarchical structure

Probably the easiest and most logical way to construct interstitial links in an electronic publication is a hierarchical structure or, what is the same, a menu, as shown in Fig. 2.1.3.2. The hierarchical structure is great for large electronic publications, as it simulates the table of contents found in most traditional print media.

Rice. 2.1.3.2. Hierarchical structure

At the beginning of work with such an EI, a menu of the main sections appears in front of the reader. Having selected one of them, the reader goes to the list of subsections, which, in turn, leads to an expanded information on some question. Of course, the number of levels can be different, but in most cases it does not exceed three. In an EI with a hierarchical structure, the user can easily determine his current position. He can choose one of two directions of movement: up, i.e. to more general information, or down to specialized information. Typically, the home page provides an overview of the content of the EI. There should also be hyperlinks to the pages of the next level of the hierarchy.

Linear structure

The linear structure resembles a regular book. As shown in fig. 3.3, the pages of the EI follow each other, and the main page of the EI plays the role of the title page of the book. In a linear structure, there are only two hyperlinks on each page: forward and backward. You can also add a hyperlink to the main page of the publication.

In a linear structure, it is usually easy to tell where you are because of the limited ability to navigate through hyperlinks.

Rice. 2.1.3.3. Linear structure

The linear structure provides limited possibilities for the EI author to represent information and for users to navigate. It is suitable for direct transfer of a traditional edition to an electronic one. It is also advisable to use it when it is required to restrict the movement of the reader through the publication. For pictograms for the linear structure of the edition, left and right arrows are suitable.

Linear structure with alternatives

The rigidity and constraints of the linear structure can be relaxed by allowing users to deviate from the main path. In a linear structure with alternatives on one of the pages, as shown in Fig. 2.1.3.4, there can be multiple hyperlinks to linear substructures. Such linear substructures may end with the same page.

Rice. 2.1.3.4 Linear structure with alternatives

For example, suppose you are describing the installation of a software package on a computer, and all the steps of this procedure, except one, do not depend on the type of computer. The structure of such an electronic edition fits well into a linear structure with alternatives, as shown in Fig. 2.1.3.4.

Hierarchical-linear structure

Almost any book has a hierarchical linear structure. Indeed, the hierarchical component is provided by the table of contents, and the linear component is the flipping of the pages of the book. The hierarchical-linear structure in EI is better supported than in the traditional edition, since, having found the desired section in the table of contents, you do not need to remember the page number and leaf through the book, but just click on the corresponding hyperlink. In fig. 2.1.3.5 depicts an EI with a hierarchical-linear structure. The combination of linear and hierarchical structures allows the user to navigate in four directions: up, down the hierarchy, and back and forth at the same level of the hierarchy (see Figure 2.1.3.5). It should be noted that it is easy to get lost, and therefore explanations are needed for navigation: each page must have hyperlinks forward, backward, to the beginning of the EI and up. Let's think about what the transition up the hierarchy corresponds to.

Rice. 2.1.3.5. EI with a hierarchical-linear structure

Consider the following example. Let the EI have a two-level table of contents. The first level lists chapters, and the second level contains hyperlinks to each chapter for each chapter.

If we went to the main text page directly from the table of contents of the second level, then by moving up the hierarchy it is natural to understand the return to the table of contents of the second level. But what about the case when we consistently read the text of the EI and have passed from the first chapter to the second? Moving up the hierarchy, we will find ourselves in the table of contents of the second chapter, which we have not seen before, and this contradicts the properties of the hierarchical structure and therefore disorientates the reader, who believes that all transitions up the hierarchy (like all transitions down) obey the same rules ...

Two solutions can be proposed:

Refuse horizontal transitions between linear sequences. For the above example, this means that the transition from the text of the first chapter to the second is carried out only through the top level of the hierarchy.
Accompany hyperlinks with detailed comments about the pages they point to.

Network structure

The network structure is formed by an unordered set of links between pages, and the reader moves from page to page along an arbitrary route using hyperlinks. An example of a network structure is shown in Fig. 2.1.3.6.

Such electronic publications can be navigated without a specific purpose. They are convenient when the author deliberately wants to make the presentation unsystematic, simulating associative thinking or encouraging random viewing. The World Wide Web is itself a giant networked structure. Many games are networked.

It is very easy to get lost in EI with a network structure. Without an EI plan, it is difficult to establish how the page in front of you relates to the page you are navigating to. It is often difficult to find also the ratio between the current page and the page passed. In many cases, you can return to the beginning of the path only by doing all the steps in reverse order.

Rice. 2.1.3.6. Network structure of the electronic edition

The network structure is poorly suited for EIs intended to receive information on a specific issue, since the search for it can take a long time, and sometimes turn out to be unsuccessful. You can facilitate orientation in EI with a network structure in the following ways:

create a hyperlink to the main page on each page;
place on each page an EI map indicating the position of this page in the publication or any other explanations to the reader about where he is at the moment.