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Internet

The Internet is the worldwide, publicly accessible network of interconnected computer networks that transmit data by packet switching using the standard Internet Protocol (IP). It is a ‘network of networks’ that consists of millions of smaller domestic, academic, business, and government networks, which together carry various information and services, such as electronic mail, online chat, file transfer, and the interlinked Web pages and other documents of the World Wide Web.

Contrary to some common usage, the Internet and the World Wide Web are not synonymous: the Internet is a collection of interconnected computer networks, linked by copper wires, fiber-optic cables, wireless connections, etc.; the Web is a collection of interconnected documents and other resources, linked by hyperlinks and URLs. The World Wide Web is accessible via the Internet, as are many other services including e-mail, file sharing, and others.

Aside from the complex physical connections that make up its infrastructure, the Internet is facilitated by bi- or multi-lateral commercial contracts (e.g., peering agreements), and by technical specifications or protocols that describe how to exchange data over the network. Indeed, the Internet is essentially defined by its interconnections and routing policies.

Through keyword-driven Internet research using search engines, like Google, millions worldwide have easy, instant access to a vast and diverse amount of online information. Compared to encyclopedias and traditional libraries, the World Wide Web has enabled a sudden and extreme decentralization of information and data.

The Internet allows computer users to connect to other computers and information stores easily, wherever they may be across the world. They may do this with or without the use of security, authentication and encryption technologies, depending on the requirements.

This is encouraging new ways of working from home, collaboration and information sharing in many industries. An accountant sitting at home can audit the books of a company based in another country, on a server situated in a third country that is remotely maintained by IT specialists in a fourth. These accounts could have been created by home-working book-keepers, in other remote locations, based on information e-mailed to them from offices all over the world. Some of these things were possible before the widespread use of the Internet, but the cost of private, leased lines would have made many of them infeasible in practice.

An office worker away from his desk, perhaps the other side of the world on a business trip or a holiday, can open a remote desktop session into his normal office PC using a secure Virtual Private Network (VPN) connection via the Internet. This gives him complete access to all his normal files and data, including e-mail and other applications, while he is away.

History of the Internet

Originally intended to share data between a few universities and government agencies, the Internet today allows connectivity from anywhere on earth and beyond—even ships at sea and in outer space.

The history of the Internet dates back to the early development of communication networks. The idea of a computer network intended to allow general communication among users of various computers has developed through a large number of stages. The melting pot of developments brought together the network of networks that we know as the Internet. This included both technological developments and the merging together of existing network infrastructure and telecommunication systems.

The infrastructure of the Internet spread across the globe to create the world wide network of computers we know today. It spread throughout the Western nations and then begged a penetration into the developing countries, thus creating both unprecedented worldwide access to information and communications and a digital divide in access to this new infrastructure. The Internet went on to fundamentally alter and affect the economy of the world.

In the fifties and early sixties, prior to the widespread inter-networking that led to the Internet, most communication networks were limited by their nature to only allow communications between the stations on the network. Some networks had gateways or bridges between them, but these bridges were often limited or built specifically for a single use. One prevalent computer networking method was based on the central mainframe method, simply allowing its terminals to be connected via long leased lines.

A fundamental pioneer in the call for a global network, J.C.R. Licklider, articulated the idea in his January 1960 paper, Man-Computer Symbiosis.

‘a network of such [computers], connected to one another by wide-band communication lines’ which provided ‘the functions of present-day libraries together with anticipated advances in information storage and retrieval and symbiotic functions. ‘ -J.C.R. Licklider

E-mail

Electronic mail (abbreviated ‘e-mail’ or, more commonly, ‘email’) is a store and forward method of composing, sending, storing, and receiving messages over electronic communication systems. The term ‘e-mail’ (as a noun or verb) applies both to the Internet e-mail system based on the Simple Mail Transfer Protocol (SMTP) and to intranet systems allowing users within one organization to e-mail each other. Often these workgroup collaboration organizations may use the Internet protocols for internal e-mail service.

E-mail predates the Internet; existing e-mail systems were a crucial tool in creating the Internet. The Compatible Time-Sharing System (CTSS) was begun at MIT in 1961. It allowed multiple users to log into the IBM 7094 from remote dial-up terminals, and to store files online on disk. This new ability encouraged users to share information in new ways. E-mail started in 1965 as a way for multiple users of a time-sharing mainframe computer to communicate.

E-mail was quickly extended to become network e-mail, allowing users to pass messages between different computers. The messages could be transferred between users on different computers by 1966. The ARPANET computer network made a large contribution to the evolution of e-mail. There is one report which indicates experimental inter-system e-mail transfers on it shortly after its creation, in 1969. Ray Tomlinson initiated the use of the @ sign to separate the names of the user and their machine in 1971. The ARPANET significantly increased the popularity of e-mail, and it became the killer app of the ARPANET.

As the utility and advantages of e-mail on the ARPANET became more widely known, the popularity of e-mail increased, leading to demand from people who were not allowed access to the ARPANET. Since not all computers or networks were directly inter-networked, e-mail addresses had to include the ‘route’ of the message, that is, a path between the computer of the sender and the computer of the receivers. E-mail could be passed this way between a number of networks, including the ARPANET, BITNET, and NSFNET.

In the mid 1970s it was becoming apparent that as computers decreased to the size that would fit on a desktop, they might become valuable tools for increasing organizational productivity. The problem was that no one had the vaguest idea about how to use a networked system of computers and workstations productively within the office environment.

In 1982 the White House adopted a prototype e-mail system from IBM called the Professional Office System, or PROFs for the National Security Council (NSC) staff. By April 1985, the system was fully operational within the NSC with home terminals for principals on the staff. In 1991, the first e-mail from space was sent from aboard the Space Shuttle Atlantis, mission STS-43, using AppleLink running on a Macintosh Portable.

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