The application of the Internet

1. World Wide Web

The World Wide Web (also available as "network", "WWW", "W3", "web" or "Wide Web") is a data space. In this space: something as useful as a "resource" and identified by a global "Uniform Resource Identifier" (URL). These resources are transmitted to the user via the Hypertext Transfer Protocol (hypertext Transfer Protocol), which is then clicked on to obtain resources. From another point of view, the World Wide Web is an interconnected hypertext file (interlinked hypertext document) system accessed through the Web. The World Wide Web Consortium, also known as the Wide, is called the Consortium. The Massachusetts Institute of Technology (MIT) Computer Science Lab was founded in October 1994 with the title of "World Polytechnic University". The creator is Tim Berners-Lee, inventor of the World Wide Web.
the World Wide Web is often used as a synonym for the internet, but the World Wide Web is a service that runs on the Internet.
when you want to go to a Web page on the World Wide Web, or other network resources, you usually first type the Uniform Resource Locator (Uniform Resource Locator), abbreviated URL, that you want to access the Web page on your browser, or link to that Web page or network resource by hyperlink. This is followed by the server name portion of the URL, which is known as the domain Name System of the global Internet database parsing, and according to the resolution of the decision to enter which IP address (IP addresses).
the next step is to send an HTTP request to the Web page you want to access, to the server that is working on that IP address. In general, HTML text, pictures, and all other files that make up the page are quickly sent back to the user individually.
the next task of the Web browser is to display the HTML, CSS, and other accepted files to the user by adding images, links, and other necessary resources. These are the "Web pages" that you see.
200px-first_web_server.jpg's earliest network vision dates back to the distant 1980 Tim Berners-Lee-built enquire project. This is a hypertext online editing database similar to Wikipedia. Although this is very different from the World Wide Web we are using today, they have many of the same core ideas and even include some ideas from the next project Semantic web behind Berners-Lee's World Wide Web.
in March 1989, Berners-Lee wrote a "Proposal on information management", which mentions enquire and describes a more sophisticated management model. November 12, 1990 he partnered with Robert Cailliau to Robert Cario a more formal proposal on the World Wide Web. On November 13, 1990 he wrote the first webpage on a next workstation to realize the idea in his article.
during that year's Christmas holiday, Berners-Lee made all the tools necessary for a network job [6]: The first web browser (also editor) and the first Web server.
On August 6, 1991, he posted an article on the World Wide Web Project profile at the Alt.hypertext News Group. The day also marks the first appearance of the Web public service on the Internet.
The most important concept hypertext in the World Wide Web originated from several previous projects in the 1960 's. For example, Teide Nielsen (Ted Nelson) of the Semporna Project (Project Xanadu) and Douglas Ingbart (Douglasengelbart) nls. The two projects were inspired by Wanniwal Bush's "Memory Extension" (Memex) system designed for microfilm in his 1945-year paper, "Same as we think".
Another brilliant breakthrough for Tim Berners-Lee is the grafting of hypertext onto the Internet. In his book Weaving network, he explained that he had repeatedly advised the users of the two technologies that their union was feasible, but that no one had responded to his suggestion, and he had finally settled the plan himself. He invented a globally unique authentication system for network resources: the Uniform Resource Identifier.
There are many differences between the world Wide Web and other hypertext systems:
* A single connection rather than a two-way connection is required on the World Wide Web, allowing anyone to link the resource without any action by the owner. This is critical to reducing the difficulty of implementing Web servers and Web browsers compared to earlier network systems, but its side effects are chronic problems that create bad chains.
* The World Wide Web is not proprietary, unlike some applications such as HyperCard, which allows servers and clients to grow and expand independently, without the license restrictions.
on April 30, 1993, CERN announced that the World Wide Web was open to anyone free of charge. Two months later Gopher announced that it was no longer free, causing a large number of users to move from Gopher to the world wide. The World Wide Web Consortium, also known as the Wide, is called the Consortium. Founded in October 1994 at MIT's Computer Science lab. The creator is Tim Berners-Lee, inventor of the World Wide Web.
since the 40 's, people have dreamed of having a world-wide information base. Data in this database can be accessed not only by people around the world, but also by easily linking information elsewhere, so that users can easily and quickly access important information. It triggered the fifth information revolution.
with the rapid development of science and technology, People's dream has become a reality. The most popular system currently in use is called "Global Information Network www" (World Wide Web). It is formally defined as "Wwwis a Wide-area hypermedia information retrieval initiative to give universalaccess to large universe of documen Ts. " In short, www is an Internet-based computer network that allows users to access information on another computer over the Internet on a single computer. Technically speaking, the global Information Network is a collection of clients and servers on the Internet that support the WWW protocol and Hypertext Transfer Protocol HTTP (Hyper text Transport Protocol), which allows access to hypermedia files around the world, including text, Graphics, sounds, animations, repositories, and a variety of software.
In theory, the Global Information network consists of an entire internet world of over 200 million people, including all Web sites, Gopher information stations, FTP archives, Telnet public access accounts, news discussions, and WAIS repositories. So global information network can be said to be today the world's largest electronic data world, has been able to Wide web as a synonym for the internet. In fact, what we call "on the Internet", in fact, refers to the worldwide Web. WWW is the World Wide Web (Global information Network) abbreviation, also can be referred to as the Web, Chinese name is "www".
because of various organizations, scientific research institutions, universities, companies interested in research and development of information collection. It is an Internet-based query. Information distribution and management system is a dynamic format of multimedia communication that people interact with. Its formal formulation is: "A wide-area hypermedia information Retrieval original protocol, the purpose is to access a huge amount of documents." The part of WWW that has been implemented is to provide a compatible means for users on the computer network to access various media in a simple way. It is the first truly global hypermedia network that has changed the way people observe and create information. As a result, the whole world has rapidly launched a huge upsurge of research and development using www.
www was born in the Internet and later became part of the Internet, and today, www is almost synonymous with the Internet. With it, everyone who joins can instantly reach every corner of the world with a phone line plugged into your PC (which may be your portable laptop plus a mobile phone), and the world's information is at your fingertips!
www is not actually in any place in the world, in fact, the users of www give it new meaning every day. Citizens of the Internet community, including institutions and individuals, embed the information they need to publish in the form of a home page (homepage), which includes graphics, sound and other forms of media, in addition to text, and content from a variety of recruitment ads to an electronic version of the Bible, which can be said to be all-encompassing, Omniscient Home page is the main form of publishing on the Web is some HTML text (HTML is Hyper Text Markup Language, hypertext Identity language).
with the rapid development of mobile Internet, some recent experts have WAP and WWW and said. WAP is now a global fact standard for accessing wireless information services via mobile phones or other wireless terminals. The development and application of it is limitless.
a client is a program that needs something, and a server is a program that provides something. A client can request to many different servers. A server can also provide services to several different clients. Typically, a client initiates a conversation with a server. A server is typically an automated program that waits for a client request. A client is usually run as a request from a user or a user-like application. A protocol is a definition of the various ways that a client requests a server and a server to answer a request. The WWW client can also be called a browser.
The usual global information on the Internet clients mainly include: IE, Firefox, Safia, opera and so on.
in the Web, the client's tasks are:
1. Help you make a request (usually started when you click a link point).
2. Send your request to a server.
3. Report the results of the request to you by properly decoding the direct image, submitting the HTML document, and passing the various files to the appropriate "viewer".
an observer is a program that can be invoked by a WWW client to render a particular type of file. When a sound file is viewed and downloaded by your WWW client, it can only be "observed" using certain programs, such as "Media Player" under Windows.
Typically, the WWW client is not limited to making requests to the Web server, but it can also make requests to other servers, such as Gopher, FTP, news, and Mail.
Server
1. Accept the request
2. Check the legality of the request, including the security shield.
3. Obtain and make data for requests, including Java scripts and programs, CGI scripts and programs, and set the appropriate MIME type for the file to pre-process and post-process the data.
 

2. File Transfer FTP

How FTP Works

Take the file as an example, when you start FTP copy files from a remote computer, you actually launch two programs: an FTP client on a local machine: it asks the FTP server for a copy of the file. The other is the FTP server program that launches on the remote computer, and it responds to your request to transfer the files you specified to your computer. FTP uses a "client/server" approach, where the client installs FTP clients on its own local computer. The FTP client has two types: the character interface and the graphical interface. The ftp command of the character interface is complex and numerous. Graphical interface of the FTP client program, the operation to be concise and convenient more.

Simply put, the server that supports FTP protocol is the FTP server, the following describes what is the FTP protocol (File Transfer Protocol)

In general, the primary purpose of user networking is to achieve information sharing, documentation. I can understand that.

FTP (file Transfer Protocol, which is a very widely used communication protocol on the Internet, is designed for file transfers (including file uploads and downloads) for Internet users. To implement FTP file transfer, it must be installed at both ends of the connection to support the FTP protocol software, installed on your computer called FTP client software, installed on the other end of the server is called FTP server-side software.

The client FTP software is very simple to use, after starting to establish a connection with the remote host, and then issue a transfer command to the remote host, the remote host receives the command to give a response, and execute the correct command. The most commonly used FTP software in Windows systems is cuteftp. FTP has a fundamental limitation, that is, if the user is not registered on a host to be authorized, that is, there is no user name and password, you cannot file transfer with the host. The exception is anonymous FTP server, which allows users to log in with Anonymous as their username and email address as a password, thus allowing users to get free resources.

3. Internet News

Network news is a network-based news, with fast, multi-faceted, multi-channel, multimedia, interactive and other characteristics. Break through the traditional concept of news communication, in the visual, listening, sense to give audiences a new experience.

Brief introduction

Network news is a breakthrough in the traditional concept of news communication, in terms of visual, listening, and feeling to give audiences a new experience. It integrates the chaotic news in an orderly manner, and greatly compresses the thickness of the information, so that people get the most effective news information in the shortest time. In addition, the future of web news will no longer be limited by the traditional news publishers, the audience can publish their own news, and in a short period of time to obtain faster dissemination, and the news will become a platform for people to interact. The network news will develop at a deeper level along with the improvement of people's cognition, which will completely subvert the traditional concept of Internet news.

April 1994, China full access to the Internet, January 1995, "Chinese scholar" magazine became China's first Internet media. Since then, the Chinese network media has undergone nearly a decade of development, this stage can also be regarded as the first historical period of Chinese network media. In this historical period, China's network media business has made great strides, one of the most direct and most outstanding performance, is the network media in the news business progress.

The network news business, its birth is an extension of the traditional news business, but, after nearly ten years of development, it is constantly absorbing the traditional news business nutrients, but also gradually formed their own new face, some, even revolutionary, and may have an impact on the whole media news business development.

4. E-Mail

E-mail is a means of communication that provides information exchange electronically, and is the most widely used service in the Internet. Through the network's e-mail system, users can be at a very low price (regardless of where to send to pay the network fee), very fast way (within a few seconds can be sent to any designated destination in the world), and any corner of the World Network users contact.

e-Mail can be text, images, sounds and many other forms. At the same time, users can get a lot of free news, special mail, and to achieve easy information search. The existence of e-mail greatly facilitates the communication and communication between people and promotes the development of society.

Application of the Internet