The World Wide Web (WWW or Web for short) is the leading information retrieval service of the Internet (the worldwide computer network). The Web gives users access to a vast array of documents that are connected to each other by means of hyperlinks. With a web browser like MS-Edge, one can view web pages that may contain text, images, videos, and other multimedia, and can search for information by moving from one document to another. English computer scientist, Sir Tim Berners-Lee is regarded as having invented the World Wide Web in 1989.

Hypertext is structured text that contains logical links (hyperlinks) between nodes containing text. Ted Nelson, an American Information Technology pioneer originally coined the word “hypertext” for “non-sequential writing” around 1965. The Hypertext Transfer Protocol (HTTP) is the foundation of data communication for the World Wide Web. It is an application protocol that enables the exchange or transfer of hypertext. Hypertext Markup Language (HTML) is the main markup language for creating web pages and other information.

A web browser is software used to download and display web pages on a computer. It can communicate with a web server holding the web pages using the HTT Protocol to download the pages requested, usually by clicking on a hyperlink. A browser can translate HTML, the web page language, into the content that is displayed in the browser window. An information resource or a website is identified by a Uniform Resource Identifier (URI) – a kind of “address” that is unique to each resource on the Web. In most web browsers, the URI of a web page is displayed on top inside an address bar. Hyperlink present on a web page enables users to easily navigate their browsers to related resources. The major web browsers are Google Chrome, Mozilla Firefox, MS Edge, Opera, and Safari.

A Uniform Resource Locator (URL), also known as a web address, is a specific character string that constitutes a reference to a resource. It is technically a type of URI, but in many technical documents and verbal discussions, URL is often used as a synonym for URI.

Although the WWW is often referred to as the Internet, the two are not the same. The internet is a global system of computer networks that are interconnected by a network of telephone lines, cables, and satellite connections. The World Wide Web is the collection of linked pages that are accessed using the Internet and a web browser. In short, the WWW is a subset of the Internet.

A website is a set of related web pages hosted on a web server. The site structure includes a home page with most of the links to the site’s web content, and supplementary about, contact, and link pages. The pages of a website can be accessed from a URL that is typed or displayed in the address bar of a web browser. The URLs of the pages organize them into a hierarchy. Some websites require a subscription to access some or all of their content. Examples of subscription websites include many business sites, academic journal websites, gaming websites, file-sharing websites, web-based email, and social networking websites.

A user may view a page on the  WWW normally by typing the URL or web address of the page into the address bar of a web browser. The web browser then initiates a series of communication messages, behind the scenes, in order to fetch and display the desired web page. A user may also view the page by following a hyperlink to that page. HTTP functions as a request-response protocol in the client-server computing model. A web browser, for example, maybe the client and an application running on a computer hosting a website may be the server. The client submits an HTTP request message to the server. The server returns a response message (in the form of HTML files and other content), to the client.

A web server is a computer system that stores websites on the Internet and delivers web pages to viewers upon request. This means delivery of HTML documents and an additional content that may be included in a document, such as images, style sheets and scripts. Every web server has an Internet Protocol (IP) and address and possibly a domain name. For example, if the user types the URL http://www.information.com/index.html in the browser, the browser sends a request to the Web server, whose domian name is information.com. The server then fetches the page named index.html and sends it to the user’s browser.

An Internet Protocol  (IP) is a uniques string of numbers separated by periods or dots that identifies each computer using the Internet Protocol to communicate over a network. IP address are binary numbers, but they are usually stored in text files and displayed in human-redable notations, such as 172.16.254.1.

A domain or domain name is an online identity for an organization or a company, which allows internet users from around the world to locate and browse its web site 24 hours a day, seven days a week. A domain is also a group of computers and devices on a network that are administrated as a unit with common rules and procedures. All devices sharing a common part of the IP address are said to be in the same domain. Domain names serve as humanly memorable names for Internet participants, like computers, networks, and services. Organizations can choose a doman name that corresponds to their name, helping Internet users to reach them easily. Every domain name has a suffix that indicated the type of organization or geographical location. For example:

A proxy server is a computer that functions as an intermediary between a web browser (such as Chrome) and the Internet. Proxy servers help improve website performance by storing a copy of frequently requested webpages. When a browser requests a webpage stored in the proxy server’s collection (it’s cache), it is provided by the proxy server, which is faster than going to the web. Proxy servers also help improve security by filtering out some web content and malicious software. Proxy servers can also be used to filter requests. For example, a company might use a proxy server to prevent its employees from accessing a specific set of web sites.

The domain name system (DNS) is a standard technology for managig the names of Web sites and other domains. It is a hierachical distributed domain names to various types of data, such as Internet Protocol (IP) address. DNS allows you to use friendly names, such as www.microsoft.com, that helps to locate computers and other resources on a TCP/IP based network. DNS is an Internet Engineering Task Force (IETF) standard.