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We have already stated that the Internet is much more than the WWW, and that the network has a series of services that, to a greater or lesser extent, have to do with information functions, computer networks and communication and interaction services. Some of the services available on the Internet, apart from the Web, are remote access to other computers (through telnet or following the client / server model), file transfer (FTP), email (e-mail), electronic bulletins and newsgroups (USENET and news groups), distribution lists, discussion forums and online conversations (chats).
Email and Usenet newsletters were the first forms of communication used over the Internet, but today the network offers a wide range of tools and contexts for document access and retrieval, communication and interaction. In addition, the access and distribution of information is no longer limited to ASCII code text, as in the early days of the Internet, but it covers all morphologies of information: text, image, audio, video, audiovisual resources, etc. On the Internet you can also listen to the radio, watch TV, attend a concert, visit a museum or play online. The use of the Internet has grown exponentially thanks to many of these uses and, especially, the ease of use that the World Wide Web itself allows today.
Thus, there are services that allow the exchange of personal messages (email, newsgroups, distribution lists, forums, etc.), others suitable for interaction through real-time conversations (chats) and others dedicated to the supply and access to information (World Wide Web, FTP, etc.).
In the specific field of documentation, we are interested to know that there are or have existed numerous tools on the Internet that facilitate the location of information or access within the network, such as: Whois, X.500, Gopher, Archie, WAIS and WWW. Currently, the vast majority of these tools have evolved and are now accessible within the Web. For example, the telnet protocol that facilitated the connection of a remote computer to an open network and that was used to connect to large catalogs of libraries, documentation centers and databases, has practically disappeared, since it has been imposed almost exclusively the client / server model converting the Internet into a network of much more open networks, with computers (both servers and clients) much more powerful. Today it is possible to access these large catalogs through the interface offered by web browsers.
The services that the Internet offers today have not only multiplied, but have evolved towards new and improved functions and have gained in ease of use and management. This change has contributed not only the transfer speed of the bits that modern modems and routers allow, and the greater efficiency and capacity of telecommunication lines with a high bandwidth, but also improvements in software and applications ( databases integrated in the Web, search engines, intelligent agents, etc.) and in the hardware (greater storage capacity and memory, exponential increase in the speed of the processors, ability to process all types of data, not just the textual ones , but also multimedia data, etc.). The user no longer has to operate with complex commands and algorithms, but using the mouse over icons and graphical interfaces and even with the voice, and through natural language.
According to the study conducted by Peter Lyman and Hal R. Varian of the School of Information Management and Systems of the University of California, Berkeley, the daily activities carried out on the Internet are the following:
DAILY ACTIVITIES ONLINE
ACTIVITY
% of those with Internet access
Date of the data
Send mail
52
March-May 2003
Get news
32
March-May 2003
Use a search engine to obtain information
29
January 2002
Surf the Web to have fun
2. 3
March-May 2003
Search information about a hobby
twenty-one
March-May 2003
Do a search on the Internet to answer a specific question
19
September 2002
Do some type of checking for work
19
November 2002
Check a product or service before buying it
19
December 2002
Check the weather
17
March-May 2002
Send an instant message
14
March-May 2003
Source: http://www.sims.berkeley.edu/research/projects/how-much-info-2003/internet.htm and
Pew Internet and American Life Project (own translation)
The main services or applications that we can find on the Internet are:
world Wide Web
News Groups (News, News Bulletins)
Distribution lists
Web Forums
Weblogs, blogs or blogs
File transfer FTP (File Transmission Protocol)
Exchange of P2P file
Archie
Chats or IRC (Internet Relay Chat), audio and videoconference, instant messaging and telephone calls via the Internet
Telnet
Gopher
Veronica
Wais
M * Ds
Social networks or Social networking
Wikis
Syndication of contents (RSS, Atom, XML)
Spaces or Spaces
world Wide Web
The World Wide Web, Web, WWW or W3, is based on the HTML language (HyperText Markup Language) and the HTTP protocol (HyperText Transfer Protocol). The hypertext protocol was developed by the European Laboratory of Particle Physics CERN by Tim Berners-Lee around 1990.
The HTTP protocol is the most powerful protocol that currently exists on the Internet, since it allows the same type of operations as the GOPHER system, but with the advantage of being able to acquire and visualize easily and quickly all types of morphologies. information (video, audio, text, software, etc.).
The possibility of joining the different existing files in the Internetred services through the URL (Universal Resource Locator), converts the web server to this tool into a fundamental engine in the development of the Internet. In practice, it is the most used service in the network. It is not only a deposit of information, but also a form of access, search and recovery.
To be able to use the Web service, two components are needed: the server and the client. The WWW server or host is the company that puts at your disposal the machines where the WWW pages are hosted, following the standard defined by the HTML language (today many other languages have been developed for the Web with hypertext possibilities and other added functionalities) and , on the other hand, is the client or user's computer. If the user wants to access these pages, he has to use a program (WWW client) that reads the WWW pages and interprets their meaning. These WWW programs or clients are the browsers and are those that allow the user's computer to interpret the HTML language. The browsers Internet Explorer and Netscape Navigator are the most used, but there are a large number of them with different views and features, and they can also be downloaded for free from the Internet to install them on our computer.
web in Netscape web browser in Internet Explorer browser
The same web seen in the Netscape Navigator browser (left)
and in the Internet Explorer browser (right)
The unique address of a document on the World Wide Web is called URL -Uniform Resource Locator- and consists of the following elements:
HTTP (Hyper Text Transfer Protocol), the protocol for exchanging data between the client and the server.
The Internet address of the server that broadcasts the documents. This address is unique throughout the network, it is the TCP / IP address of the machine. It consists of a series of numbers like 132.248.170.90, but since they are difficult to memorize, a DNS (Domain Name System) table is used that solves the relationship between the numeric address and the symbolic name of the machine and the network to which it belongs. (let's give a fictitious example: 142.246.150.60 is the address of the machine hypertext.arsys.info in which "hypertext" represents the name of the machine and "arsys.info" the name of the network).
The directory tree (path or path) that leads to the document.
The name of the document that will always have the extension .html or .htm.
The most common syntax is the following:
protocol: // server_name / directory / subdirectory / name_of_document.htm
We will not expand here in the description of the World Wide Web, since, being the hypertext par excellence, the WWW is analyzed in a separate half-chapter.
However, we do want to point out that many of the Internet services lend themselves today to the formulation of the World Wide Web Interface, due not only to its hypermedia features - which offer a pleasant and easy-to-use design, as well as providing possibilities multimedia-, but also due to the interactive and dynamic features that the Web itself offers today. The hypertext and hypermedial Web seems to have taken a more advanced step towards Web oriented databases and the Web oriented to objects. The development of languages and interface components (Java, PHP, CGI, ASP, PERL, Javascripts.) That allow the possibility of programming applications, the connectivity with these databases and the existence of dynamic elements to access different applications presenting themselves to the user of a visually attractive and easy to use form, they have made the World Wide Web a very powerful tool to carry out all kinds of services on the Internet.
The use of electronic mail through the Web, online discussion forums, chats and videoconferencing through the Web, publication and consultation of blogs, downloading of files (text, image, audio, video, e-books, etc.). ), download of programs and applications, response to online forms for all types of purposes: subscriptions, monetary transactions, reservation of tickets for means of transport, booking of tickets for movies, theater, hotels, etc; establishment of relations between the Administration and citizens - and vice versa - through the implementation of electronic democracy, consultations and administrative procedures, bank payments, etc; television, radio and online press; access to libraries, museums and digital documentation centers through the Web; auctions and online purchases; financial and banking management; consult dictionaries, encyclopedias and other online reference works; online translation, automatic summaries of documents, creation of online web pages and transfer of files via FTP via the Web, access and retrieval of documents through the use of today's powerful search engines and intelligent robots and agents, thanks to the advances in markup languages by content (metadata, RDF, OWL, etc.) and the development of the Semantic Web, etc. All these possibilities, together with the recent developments of the so-called web services and Web 2.0 have turned the Web into the largest center of information, communication, interaction and existing services, and a center of global dimension and access.
Here are some examples of services provided through the Web, taking advantage of the hypermedia and dynamic possibilities of the Web as an interface:
Web of the Spanish Tax Agency web of Iberia
Main page of the Spanish Tax Agency (offers information and queries and the possibility of making the income statement online): http://www.aeat.es/ and Home page of the Iberia company offering consultation and booking of flights online: http://www.iberia.es/
street of the Ayto of Madrid El Corte Inglés
City of Madrid. Callejero y Plano de Madrid, with location and services locator. http://www.munimadrid.es/Principal/indexplano.html and Main Page of El Corte Inglés to make purchases online. http://www.elcorteingles.es/
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The first way to transmit information through the Internet was the protocols in ASCII code, where users could send each other pertinent data from computer to computer. This gave rise to today's most widely used e-mail (e-mail), perhaps the most used Internet service client-server that allows to send timely information and quickly. Currently this protocol has evolved from sending messages only in text format, to the transmission of elements in graphic formats, audio, video, HTML, etc. thanks to the MIME protocol (Multipurpose Internet Mail Extension), a system that allows to integrate binary files (images, sound, executable programs, etc.) within an email message.
The electronic mail is not more than an electronic message sent from a computer to another one, already they are personal messages, labor, commercial, etc. The content is to the taste of the person sending the message. You can also send messages with attachments and you can attach all kinds of documents and files (text, images, etc.) or even programs. This is the cause of many of the viruses that run through the network. There are programs like UUencode that convert a binary file, such as a photo or graphic, into an ASCII text file, so that it can be sent as an attachment in an email or downloaded from a discussion group. Once the message is received, UUdecode returns the file to its original format.
In the same way that a letter goes through several post offices before arriving at its destination, the e-mails pass from one computer to another (mail server) or mail server, to another as they travel over the Internet. When they arrive at the destination mail server, they are stored in an electronic mailbox until the recipient accesses it. This whole process takes a few seconds.
To receive or send emails you only need access to the Internet through any Internet Service Provider (ISP) and an account opened on a mail server. The mail server will give us an address and an access code. Almost all Internet access providers (ISPs) and major online services offer one or more email addresses with each account. Messages are downloaded through the SMTP server that uses the Simple Mail Transfer Protocol (Simple Mail Transfer Protocol) or Simple Mail Transfer Protocol, which, in conjunction with the server and the POP protocol (Post Office Protocol) or Office Protocol Correos, used by personal computers to manage email, will allow us to download messages to our computer. It also requires a mail program (usually the same as for the news) to manage the accounts, download and view the emails. The main browsers usually have mail managers incorporated. The main programs to manage mail can be seen in the following table:
EMAIL PROGRAMS
Eudora http://www.eudora.com
Netscape http://www.netscape.com
Mozilla http://www.mozilla-europe.org/es
Outlook http://www.microsoft.com/outlook/
Outlook Express:
Pegasus http://www.pmail.com
Yahoo Pops http://yahoopops.sourceforge.net/
An email consists of two main parts. Example of an email:
The header: contains the name and address of the recipient, the name and address of other recipients who receive a copy and the subject of the message. Some email programs also show the name, address and date of the message.
The body of the message: contains the message itself.
Email addresses on the Internet generally consist of two main parts:
user@hipertexto.info
First appears the name of the user that matches the mailbox of the recipient, followed by the sign of at @ and then the name of the host or server, also called domain name. Finally, and preceded by a point, the domain type (.es .com .info ...) appears.
But in addition, email can be served via the World Wide Web. WebMail is served through the Internet Message Access Protocol (IMAP) protocol or Internet Message Access Protocol. While the POP3 protocol (Post Office Protocol version 3) is used to download messages on our computer and read them offline, the IMAP protocol is used to read messages online since they are stored on the server and are not downloaded to the server. client computer. This allows access to messages at any time even if we are not in front of our own computer. In addition, the IMAP protocol allows you to obtain message headers in order to download only those that interest us.
Mail and messaging through the World Wide Web have grown increasingly in recent years, as can be seen in the following table:
Messages through the World Wide Web
Year
E-mails per day
E-mails per year
1999
5 billion
1.4 trillion
2000
10 billion
2001
2002
14.9 billion or 31 billion
4 trillion
2003
2004
2005
2006
60 billion
Source: http://www.sims.berkeley.edu/research/projects/how-much-info-2003/internet.htm
and IDC via Channel One Market Overview http://one.ie/report/email/marketoverview.asp (own translation)
However, a threat looms over this new medium. If in December 2001 it was calculated that 8% of emails were unsolicited emails, in 2006 we found that the fearful spam amounted to 62% of messages.
And although there is no complete directory of email addresses on the Internet, there are some directories and search engines, such as:
Listin.com The email directory in Spanish. http://www.listin.com/
Yahoo Find your people http://espanol.people.yahoo.com/
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News Groups / News Bulletins (News and USENET)
Newsgroups or newsgroups news can be considered as an extension of the electronic mail but, unlike it, it is a public and universal system of distribution of electronic messages grouped by discussion topics in an asynchronous system and that imitate a bulletin or bulletin board where users can leave their messages or read the ones that are published on that subject, as they are available on a server. To access the newsgroups, a client program is required that allows access to the server where they are located. This server stores the messages and it is necessary to use a news reader program to be able to consult them.
The BBS or news bulletins use a technology with a similar functioning: users send news to a common "bulletin board", which is consulted by the participants. Since the BBS Usenets only support text, this type of interprofessional communication is no longer used, although at the time it played a decisive role as a means of information.
The newsgroup service is usually offered by the same servers that provide access to the Internet and email accounts and the news is received using the same program to receive email. The news uses the NNTP protocol (Network News Transfer Protocol) and is also known as the USENET (USEr NETwork) since this was one of the first groups created to debate among Unix professionals and programmers, along with those of BITNET ( Because Its Time Network), those of UUCP (Uni Unix Copy Protocol) and those of FidoNet (a network based on communications between PCs over telephone lines), but there are thousands of newsgroups on the most varied topics.
Here is a compilation of newsgroups:
esp.charla.ecologismo
es.humanidades.literatura
es.humanidades.gramatica
es.misc.anuncios.trabajo.ofertas
es.astrophysics.telescope
es.ciencia.zootecnia.vacuno
alt.comp.linux
alt.movies.luis-bunuel
alt.movies.hithcockes.charla.utopia
es.comp.virus
es.rec.naturismo
alt.cyberespace.rebels
alt.cyberpunk.literature alt.feminism
alt.books
alt.sex.fetish.head
librariansoc.libraries.talk
comp.internet.library
alt.binaries.e-books
alt.animals.dog.collies
bionet.ecology.phsiology
netscape.public.mozilla.documentation
alt.culture.usenet
gov.us.usenet.admin
The names of the news groups follow a hierarchical structure that is separated by points as the specialization and the thematic scope are developed. For example:
es.rec.musica.grupos.beatles
es.rec.juegos.ajedrez
es.ciencia.medicina.depresion
esp.comp.linux.programation
microsoft.public.es.es.soporte.entre.usuarios.internet
The purpose of this form is to adapt the name to the topic so that the users know the area of interest that the subject of discussion deals with. If the language is different from English, the name of the group usually includes or is preceded by the initials of the language in question, for example:
japan.netwes
it.comp.java
fr.sci.psychology
The news groups that are developed in the Spanish language include "es" or "esp". The abbreviations for the most used topics are: alt (for alternative themes), soc (for society), sci (for science), rec (for entertainment), comp (for computation), gov (for the US government), misc (miscellaneous), etc.
In the field of hypertext there is the newsgroup: alt.hypertext
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Distribution lists
After the e-mail, distribution lists emerged, also known as discussion lists, mailing lists, discussion forums or discussion groups. The idea was to centralize the information in one node (server of the list) so that it was transmitted among several users. In this way, information that was previously accessible only to users who communicated with each other, could be generalized to other potential users who had previously subscribed to that information point.
A distribution list is not more than a group of e-mail users who, through a software or program of massive diffusion of e-mails that is in a server, can send and receive simultaneously, the messages sent to the server by any of the users or participants subscribed to the list. The most popular list distribution managers are "Majordomo" and "Listserv", and the subscriber can send or receive messages through any email program. It is estimated that the majority of users, 30%, use LISTSERV and that it is used to send 25 million messages per day, in approximately 300,000 mailing lists. It is estimated that the message distribution lists manage a total of 30 billion messages per year. (http://www.sims.berkeley.edu/research/projects/how-much-info-2003/internet.htm). Another statistical source is ListServ Statistics: http://www.lsoft.com/ltop/ltop-main.html that as of July 3, 2004, reported that there were 343,094 lists with more than 105 million users and 22 million daily messages. For example, the eListas.Net server hosts, in May 2006, more than 30,000 lists in Spanish and has more than 22 million subscribers.
The group of users or subscribers that participate in a list usually belong to a scientific or professional community that intends to share a debate or discussion on a specific topic and the servers are commonly set in motion by scientific or academic institutions.
The lists can be open and free of subscription or closed or limited to people who belong to a professional group or who meet certain conditions. Usually the option is given that the messages sent to the list can be deposited in the server to consult them retrospectively or to receive them in the subscriber's own email program. Many lists are moderated by a person who is responsible for maintaining and organizing the debate or promoting the topics of discussion. In some cases the moderator acts as a filter, since the messages arrive first at his mailbox and he is the one who forwards the appropriate messages to the list and screens the inadequate ones.
The form to sign up or subscribe to a group or discussion list follows the following format:
subscribe <node> <name of the discussion list> <username>
This communication system raises problems of saturation since it generates excessive traffic because a message is sent to all those users subscribed to the discussion group. In addition, it is very common to receive spam or spam and it is also possible to transmit computer viruses through this medium. These problems can be solved using moderators who filter the lists or using another type of similar communication such as the news. In the news the information is centralized and remains in the server computer to which we can connect to see the header of the messages and download only those that interest us. In the lists, each and every message arrives, by email, to the computers of the subscribers.
There are lists of all kinds of topics. In Spain, the lists managed by RedIris stand out, the academic and research network of the CSIC. You can see the directory of these lists (more than 400), the topics, the form of operation and subscription and the online subscription from the web: http://www.rediris.es/list/. Other website that manages and allows creating or subscribing to discussion lists is: http://www.eListas.net/, where there are more than 30,000 distribution lists, newsletters and professional newsletters. Some of these lists are public, but others need a subscription.
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