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Guys, welcome to the course "Web technologies and web design for beginners" and in this podcast
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we gonna talk about the Internet itself, its structure and what's under the hood.
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The Internet is a worldwide system of unified computer networks for storing and transmitting information.
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The Internet consists of many thousands of corporate, academic, government and home computer networks.
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In order for all computers in different networks to communicate with each other they must use the same protocol.
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The protocol in this case is a set of rules for data transmission between the nodes in a computer network.
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The Internet in its basis has many different data transmission systems, each of which is based on its own set of transmission protocols.
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For example DNS servers or domain name server server is something that provides the possibility
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of using mnemonic names for addressing network nodes instead of numerical addresses, which are hard to understand.
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Also there is electronic mail also known as email which provides the possibility of exchanging messages between two or more subscribers
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FTP service in its turn is a file archive system that provides storage and transfer of files of various types.
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Telnet service designed for controlling remote computers.
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World Wide Web is hypertext or hypermedia system designed to integrate various network resources in a single information space. 
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Streaming multimedia which is a service for continuous transmission
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of audio and video content between nodes in real time and many many others.
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In this course the most interesting for us is so-called World Wide Web.
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The World Wide Web or W3 is a distributed information system that provides access to interconnecting documents
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via HTTP or hypertext transfer protocol which are located on various nodes and connected to the Internet.
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The World Wide Web uses the Internet infrastructure for interaction between server and client...
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...and it's built on the client-server architecture.
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The nodes of the World Wide Web are web servers.
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A web server is a network application that serves HTTP requests from clients.
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A web server accepts requests and returns responses along with the text page, image, file, media stream or other data that been requested.
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Web servers are the basis of the World Wide Web and the repository of hypertext information.
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Hypertext is a form of text organization, in which its fragments are not presented in the linear sequence
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but a system has clearly indicated possible transitions and connections between them. 
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Documents presented in a form of hypertext are called web pages.
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Several web pages united via common theme, design, connected by hypertext links and located on one web server are called a website.
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There are special programs - browsers - that are used to download and view websites.
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Browser or web browser is a client software for accessing web servers using the HTTP protocol and viewing web pages.
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The main task of the browser is to receive process and display hypertext documents.