Internet and Related Technology

Content:

• Introduction
• WWW
• URL
• Domain Names
• Email
• Chat
• VoIP
• Website
• Web Page
• Web Server
• Web Hosting
• Web Browser
• Browser Add-on Extension
• Browser Plug-in
• Cookies

Introduction:

Internet is described as a network of networks, an example of Wide Area Network (WAN).
The Internet works through a packet routing network in accordance with the Internet Protocol (IP), the Transport Control Protocol (TCP) and other protocols.

WORKING:

Computers or smartphones get linked to the internet using phone line/Mobile ISP (Internet Service Provider) and usually become a part of LAN. This LAN is further connected to ISP using a high speed phone line like T1 line (1.5mbps), whereas a normal phone line or modem typically handles 30,000 to 50,000 bits per second.
ISPs then connect to larger ISPs which maintain fibre optic backbones for an entire region. Backbones around the world are connected through fibre optic lines, undersea cables or satellite links. In this manner, every computer on the internet is connected to each other for communication and sharing of resources.

WWW (World Wide Web):

The internet is a huge network of computers all connected together. The World Wide Web (‘www’ or ‘web’ for short) is a collection of webpages found on this network of computers. Our web browser uses the internet to access the web.

The World Wide Web is a way of exchanging information between computers on the internet through a huge collection of multimedia documents and elements. World Wide Web was created by Timothy Berners Lee in 1989 at CERN in Geneva.

DEF: WWW is a set of programs and protocols that allows the user to create and display multimedia web pages and is linked to the internet.

URL(Uniform resource locator)

URL helps in locating a particular website or a web page, for example, http://www.cbse.nic.in/academics.html is a URL for a specific website. In this URL, ‘http’ stands for hypertext transfer protocol, and ‘www.cbse.nic.in’ indicates the IP address or the domain name where the source is located. ‘academics.html’ specifies the name of the specified html document on the website of CBSE.

Domain Names:

To communicate over the internet, IP addresses is used but we use webaddress to find a resource on the internet. Domain names make it easier to resolve IP addresses into names, for example, cbse.nic.in, google.com etc. It is the system which assigns names to some computers (web servers) and maintains a database of these names and corresponding IP addresses.

A domain name consists of the following parts:
• Top-level domain name or primary domain name
• Sub-domain name(s)

For example,
In the domain name cbse.nic.in:
in is the primary domain name
nic is the sub-domain of in
cbse is the sub-domain of nic

Few Domain Names
·com – Commercial business
·edu – Educational institutions
·gov – Government agencies
·org – Organizations (non-profit)
.in – India

Email (Electronic mail):

Short for electronic mail, e-mail or email is information stored on a computer that is exchanged between two users over a network. It is a fast and efficient way to communicate with multiple users at the same time and is the cheapest and fastest method to send files and other information across the network. The basic purpose of using email is to send and receive messages

Some Features of email:
• Automatic/default reply to messages.
• Auto-forward and redirection of messages.
• Facility to send copies of a message to many people.
• Automatic filing and retrieval of messages.
• Addresses can be stored in an address book and retrieved instantly.
• Notification if a message cannot be delivered.

Chat:

Chatting is a method of internet conversation. It enables people connected anywhere on the internet to join in live discussions. Chat sessions allow many users to join in the same free-form conversation, usually centred on a discussion topic. The examples of chatting software are MSN Messenger, Yahoo Messenger, IRC (Internet Relay Chat), Pidgin, etc.

VoIP (Voice over Internet Protocol):

Voice over Internet Protocol (VoIP) is a technology that allows us to make voice calls using a broadband internet connection instead of a regular (or analog) phone line. VoIP services convert voice into a digital signal that travels over the internet.

Advantages
• Less cost
• Accessibility
• Better voice quality
• Extra/Less expensive features

Disadvantages
• Reliable internet connection required
• Power outages/Emergencies
• Latency

Common examples of VoIP apps are Skype, WhatsApp, Google Hangouts, Viber, Facebook Messenger etc.

Website:

A website is a collection of various web pages, images, videos, audios or other kinds of digital assets that are hosted on one or several web servers. The first page of a website is known as home page. Examples of various websites are: cbse.nic.in, google.com, amazon.in, etc.

Web Page:

A web page is an electronic document/page designed using HTML. It displays information in textual or graphical form. Traversal from one web page to another web page is possible through hyperlinks.

Types of webpage
• Static web page: A web page which displays same kind of information whenever a user visits it is known as a static web page. A static web page generally has .htm or .html as extension.
• Dynamic web page: An interactive web page is a dynamic web page. A dynamic web page uses scripting languages to display changing content on the web page. Such a page generally has .php, .asp, or .jsp as extension.

Web Server:

A web server is a server that stores web pages and when a web client sends any request to a server, the server responds to the request and displays the requested web pages. A web server is a program that runs on a computer connected to the internet. Web server waits for a request, finds the documents and generates information, if required, and sends it back to the browser that requested for it. A single web server may support multiple websites, or a single website may be hosted on several linked or mirrored web servers.

Web Hosting:

Web hosting is a service which is provided by companies to its clients to allow them to construct their own websites which are accessible to the internet users via World Wide Web. Such companies are known as web hosts. These companies provide space on a web server they own for use by their clients as well as provide internet connectivity.

Web Browser:

It is a software that helps in accessing web pages and, thus, is also called web client. It helps the user to navigate through the World Wide Web and display web pages. Some popular web browsers are: Mozilla Firefox, Opera, UC browser etc.

Browser Add-on Extension:

A browser extension is a small software module for customizing a web browser.

Browser Plug-in:

A plug-in is a piece of software that manages internet content that a browser is not designed to process. Graphics in .gif or .jpg-format are usually automatically displayed by the browser. For other file types you may need a special plug-in (also known as add-ons or extensions).

COOKIES:

A cookie is also known as an HTTP cookie, web cookie, internet cookie or browser cookie. When the user browses any website, a cookie identifies users and prepares web pages for them which are then sent to the web server for later use. Cookie is basically a piece of data that is stored by the website on the user’s hard disk. The information is stored in the form of name value pair. Generally, the cookies folder is stored in c:\windows\cookies.

References:

• NCERT for class 11 CS