How INTERNET Works?

The Internet was created by the Advanced Research Projects Agency (ARPA) and the U.S. Department of Defense for scientific and military communications.

The Internet is a network of interconnected networks. Even if part of its infrastructure was destroyed, data could flow through the remaining networks.

The Internet uses high-speed data lines, called backbones, to carry data.  Smaller networks connect to the backbone, enabling any user on any network to exchange data with any other user.

TAKE A MOMENT TO THINK ABOUT HOW AMAZING THE INTERNET IS

       -          It’s always on.

       -          It is “Free”.

       -          you can get messages to anywhere in the world instantaneously.

       -          you can communicate for free, including voice and video conferencing.

       -          you can stream music, movies, games.

Internet was not designed top-down by a single company or government organization it evolved many alternative technologies/protocols were proposed and tried out eventually, the best was identified and adopted in a democratic Way.

when new people joined, they had to use whatever protocols everybody was using, until it grew into a standard. it is decentralized no one owns it or controls it.

HOW THE INTERNET WORKS?

The single most important fact to understand about the Internet is that it can potentially link your computer to any other computer. Anyone with access to the Internet can exchange text, data files and programs with any other user. For all practical purposes almost everything that happens on the Internet is a variation of one of these activities. The Internet itself is the pipeline that carries the data between computers.

INTERNET

A network is a group of connected computers that can interact with each other and share resources.

The internet is a large network that spans the entire Earth. It is actually a network made up of many smaller networks that are all combined.

The internet is more than just web pages and the WWW (World Wide Web). The internet includes the www, newsgroups, email and other shared resources. So, the world wide web is a part of the internet.

THERE ARE TWO MAIN TYPES OF COMPUTER NETWORKS

(LAN) Local Area Network

A LAN is two or more connected computers sharing certain resources in a relatively small geographic location, often in the same building. Examples include home networks and office networks.

WAN (WIDE AREA NETWORK)

A WAN Typically consist of two or more LAN a computer is further apart and are linked by Telephone lines or radio Waves. The internet is the larges wide area network (WAN) In existence.

THE WORLD WIDE WEB (WWW)

When most people think of the internet, the first thing they think about is the World Wide Web. Nowadays, the terms "internet" and "World Wide Web" are often used interchangeably—but they're actually not the same thing.

The internet is the physical network of computers all over the world.

The World Wide Web is a virtual network of web sites connected by hyperlinks (or "links"). Web sites are stored on servers on the internet, so the World Wide Web is a part of the internet.

HTML

The backbone of the World Wide Web is made of HTML files, which are specially-formatted documents that can contain links, as well as images and other media. All web browsers can read HTML files. In addition to HTML, it's also very common for websites to use technologies like CSS (Cascading Style Sheets) and JavaScript to do more advanced things.

URL (Uniform Resource Locator)

To get to a web page, you can type the URL (Uniform Resource Locator) in a browser. The URL, also known as the web address, tells the browser exactly where to find the page. However, most of the time, people get to a web page by following a link from a different page or by searching for the page with a search engine.

The World Wide Web was created in 1989 by Tim Berners-Lee, a software engineer. Before then, computers could communicate over the internet, but there were no web pages.

URL is what you type into your browser to request a page. The URL contains the domain name, and additional path information and the protocol. http (hypertext transfer protocol) tells the browser that you are requesting a document created using hypertext what we will be writing our web pages with.

Most browsers do not require you to write http://   or even www. before typing in the rest of the address.

For example, http://www.google.com should be the same as typing google.com

TCP/IP THE UNIVERSAL LANGUAGE OF THE INTERNET

The Internet works because every computer connected to it uses the same set of rules and procedures (protocols) to control timing and data format. The protocols used by the internet are called Transmission Control Protocol/Internet Protocol universally abbreviated as TCP/IP.

These protocols include the specifications that identify individual computers and that exchange data between computers. They also include rules for several categories of application programs so programs that run on different kinds of computers can talk to one another.

TCP/IP software looks different on different types of computers but it always presents the same appearance to the network. It does not matter if the system at the other end of a connection is a supercomputer, pocket size PC or anything in between as long as it recognizes TCP/IP protocols it can send and receive data through the internet.

WEB PAGE

A web page is a single file or page on the world wide web that can display images and text, links to other web pages and can be designed to be interactive.

A web page is a document that is suitable to act as a web resource on the World Wide Web. In order to graphically display a web page, a web browser is needed. This is a type of software that can retrieve web pages from the Internet

WEB SITE

A web site is a collection of two or more connected or linked web pages.

A website is a collection of related network web resources, such as web pages, multimedia content, which are typically identified with a common domain name, and published on at least one web server. For Example, Google.com, Amazon.com etc.

BROWSER

A browser is a program that allows a user to view web pages on the World Wide Web.

A web browser is a software application for accessing information on the World Wide Web. Each individual web resource, such as a web page, image, or video, is identified by a distinct Uniform Resource Locator, enabling browsers to retrieve these resources from a web server and display them on a user device. Different browsers display web pages in different ways.

THE MOST POPULAR BROWSER.

       -          Google chrome

       -          Mozilla Firefox

       -          Internet explorer

       -          opera

       -          Safari

THERE ARE TWO TYPES OF MACHINES

       -          A server is a computer that shares files and other resources such as a printer with other computers on a on a network.

       -          A client is a computer on a network that accesses files or resources on another computer (server).

A computer can be both a client and a server at the same time. So, the world wide web is a large network made up of many servers and clients. The servers are storing the web sites, and the clients are viewing those web sites.

There are many servers around the world that store web pages for the world wide web. Every computer whether it’s a server or client is given a unique identification number when it connects to the internet. This unique number is called an I.P. Address I.P Stand for Internet Protocol.

To connect to the internet and receive an IP Address for your computer, you must have an ISP (Internet Service Provider).

THERE ARE TWO TYPES OF ISP

      1)      Dial-up

       Dial-up internet access requires your computer to dial a phone number to connect and is very slow.

     2)      Broadband

      Broadband internet access is always connected, and has much faster speeds for loading web pages and downloading files.

TYPES OF I.P

DYNAMIC I.P

Every time that you connect to your ISP, whether by calling in to your dial-up connection or restarting your broadband modem you get a new IP address. This is called a dynamic IP address.

STATIC I.P

If your computer keeps the same IP address always and it never changes it is called a static IP address.

Servers that are storing or hosting a website have static IP addresses. This means that if you know the IP address for a server you can always find that webpage.

A DNS Server (Domain Name Service) stores that information.

SUMMERY

You type in the URL for a website into your browser. Your browser is connected to the internet through your ISP. It checks the ISP’s DNS server to see what IP address matches up with the domain name and where it is located. The request is sent to the server at that IP address and the web page is sent back to your browser.

FEATURES OF THE INTERNET

The popularity of the Internet is due more to content than connectivity. As a business tool it has many uses.

Email is an efficient and inexpensive way to send and receive massages and documents around the world. The www is becoming an important advertising medium and channel for distribution.

Databases and online information archives are often more up to date than any library. The Internet also has virtual communities made up of people who share interests. Most individual users connect the computers modem to the phone line and set up an account with an Internet Service Provider (ISP) providing local and regional access to the Internet backbone. Many others connect through a school or business LAN.