Main concepts about the Internet

What is the Internet?

The Internet is a global network connecting millions of computers. More than 100 countries are linked into exchanges of data, news and opinions. According to Internet World Stats, as of December 31, 2011 there was an estimated 2,267,233,742 Internet users worldwide. This represents 32.7% of the world's population.

Unlike online services, which are centrally controlled, the Internet is decentralized by design. Each Internet computer, called a host, is independent. Its operators can choose which Internet services to use and which local services to make available to the global Internet community. Remarkably, this anarchy by design works exceedingly well. There are a variety of ways to access the Internet. Most online services offer access to some Internet services. It is also possible to gain access through a commercial Internet Service Provider (ISP).

Who Owns the Internet?

No one actually owns the Internet, and no single person or organization controls the Internet in its entirety. The Internet is more of a concept than an actual tangible entity, and it relies on a physical infrastructure that connects networks to other networks.

There are many organizations, corporations, governments, schools, private citizens and service providers that all own pieces of the infrastructure, but there is no one body that owns it all. There are, however, organizations that oversee and standardize what happens on the Internet and assign IP addresses and domain names, such as the National Science Foundation, the Internet Engineering Task Force, ICANN, InterNIC and the Internet Architecture Board.

Is Web and Internet the Same?

The Internet is not synonymous with World Wide Web. The Internet is a massive network of networks, a networking infrastructure. It connects millions of computers together globally, forming a network in which any computer can communicate with any other computer as long as they are both connected to the Internet. The World Wide Web, or simply Web, is a way of accessing information over the medium of the Internet. It is an information-sharing model that is built on top of the Internet.

What is an Internet address?

An Internet address uniquely identifies a node on the Internet.  Internet address may also refer to the name or IP of a Web site (URL). The term Internet address can also represent someone's e-mail address.

An Internet Protocol address (IP address) is a numerical label assigned to each device (e.g., computer, printer) participating in a computer network that uses the Internet Protocol for communication. An IP address serves two principal functions: host or network interface identification and location addressing. Its role has been characterized as follows: "A name indicates what we seek. An address indicates where it is. A route indicates how to get there."

The designers of the Internet Protocol defined an IP address as a 32-bit number and this system, known as Internet Protocol Version 4 (IPv4), is still in use today. However, due to the enormous growth of the Internet and the predicted depletion of available addresses, a new version of IP (IPv6), using 128 bits for the address, was developed in 1995. IP addresses are binary numbers, but they are usually stored in text files and displayed in human-readable notations.

What is URL?

Abbreviation of Uniform Resource Locator (URL) it is the global address of documents and other resources on the World Wide Web.

The first part of the URL is called a protocol identifier and it indicates what protocol to use, and the second part is called a resource name and it specifies the IP address or the domain name where the resource is located. The protocol identifier and the resource name are separated by a colon and two forward slashes.

A URL is one type of Uniform Resource Identifier (URI); the generic term for all types of names and addresses that refer to objects on the World Wide Web.

The term "Web address" is a synonym for a URL that uses the HTTP / HTTPS protocol.

The Uniform Resource Locator (URL) was developed by Tim Berners-Lee in 1994 and the Internet Engineering Task Force (IETF) URI working group. The URL format is specified in RFC 1738 Uniform Resource Locators (URL).

What is the domain name?

Domain names are used to identify one or more IP addresses. For example, the domain name microsoft.com represents about a dozen IP addresses. Domain names are used in URLs to identify particular Web pages. For example, in the URL http://www.pcwebopedia.com/index.html, the domain name is pcwebopedia.com.

Every domain name has a suffix that indicates which top level domain (TLD) it belongs to. There are only a limited number of such domains. For example:

• gov - Government agencies

• edu - Educational institutions

• org - Organizations (nonprofit)

• mil - Military

• com - commercial business

• net - Network organizations

• ca - Canada

• th - Thailand

Because the Internet is based on IP addresses, not domain names, every Web server requires a Domain Name System (DNS) server to translate domain names into IP addresses.

(based on: http://www.webopedia.com)

Match the words and word combinations with their Ukrainian equivalents:

1. estimated	a) визначати вузол
2. nonprofit	b) зробити доступними
3. depletion	c) некомерційний
4. to make available	d) здійснювати нагляд
5. colon	e) урядові установи
6. а tangible entity	f) приблизно
7. to identify a node	g) вичерпування
8. to gain access	h) двокрапка
9. Government agencies	i) матеріальна одиниця
10. to oversee	j) отримати доступ