INTERNET

                       

                                       

                        The internet is a global connection of computers. These computers are connected via a huge network of telecommunication links. The internet allows you to access to a whole resource of data and information stored at different sites (called hosts) and locations around the world. The communication links which inter connect each host computer use a common method of transmission known as TCP/IP, which stands for Transmission Control Protocol / Internet Protocol.

Internet connection helps us to:
1. Read information on a wide range of topics
2. Send or receive E-mail
3. Down load useful programs such as virus detectors, file compression, decompression utility etc.
4. Share your opinions and your knowledge on a variety of topics through various new groups.
5. Chat with other people any where in the world
6. View interesting video‘s listen to music or wander through a 3-D world.

Requirements for connecting to the Internet:

a) Modem: A modem is a peripheral device that allows a computer to connect and
Communicate with other computers. Modem stands for Modulator Demodulator.

b) Web Browser: A browser is a software program that is necessary in order to view web pages on the web. Ex: Internet Explorer, Netscape Navigator, Mozilla Firefox,
Microsoft outlook express etc.

c) Telephone line: A telephone line is required to transfer data from one computer to
another. The computer is connected to a modem, which, in turn, connected to a telephone
line.

d) Subscription with Internet service provider (ISP): ISP‘s are companies that provide access to the internet. We need subscription with any ISP to get an Internet connection.
Some of the ISPs in India are VSNL, MTNL, Sify, Specrta Net etc.

World Wide Web (WWW):
It refers to the collection of information accessible on the internet. The web is similar to a library. It consists of millions & millions of pages of text, pictures, sounds and animation on various topics. These pages, called web pages are stored on different computers that are connected to the internet. The web pages have links between them i.e. when we click a certain word or picture in a page, it will take us to another page. These words or pictures that help to move from one page to another are called hyperlinks.
                A collection of related web pages is known as a web site. A web site can be accessed by means of a unique name assigned to it.
Internet was initially designed for the transmission of text basing on the protocols mentioned. In order to transmit a graphically designed web page complete with pictures, embedded sound and animation a special language was designed which is referred to as

Hyper Text Mark up Language (HTML). HTML uses special text codes to define the various elements of a web page. The WWW support a protocol called Hyper Text Transfer Protocol (HTTP). All internet servers cannot support HTTP and so the web can be regarded as a subset of the larger internet. HTTP provides a method of transmitting a professionally laid out page over the text based internet.

Uniform Resource Locator: (URL): Each web site has a unique address commonly referred to as a URL. A URL specifies the exact location of the web page on the internet.

E-Mail
E-mail or electronic mail is a service for sending or receiving messages electronically through a computer network. The electronic mail uses various technologies that support electronic transmission of text, data and graphics.

Some of the features of E-mail are
1. It is much faster than the normal mail.
    Messages can be sent within a matter of seconds   to any part in the world.
2. it can be sent to many people at the same time
3. E-mail is cheaper than a phone call and an ordinary mail
4. it can access information and file libraries on request
5. E-mail user can have a mail box which is accessed through a computer terminal
6. an E-mail message consists of two parts
     a) a header specifying the address of the sender and the address of the receiver
     b) the text of the message
7. The mailing system allows selecting messages for reading, displaying, saving, deleting,
     forwarding and replying.
8. Mailing list can be created to send the same message to a group of people

E-Mail Address: An E-Mail address consists of three parts
1. The person‘s Login name
2. @ sign
3. Domain name
A domain represents organization, network, and country name
Ex: Statisitcs@hotmial.com in this Statistics is the user name and his account is in the domain hotmail.com. Both the names are separated by the @symbol.
Search Engines:

Search engines are utilities used to search for information on the web. A user interface is provided where you can enter the word or phrase you are searching for. The search engine looks for the keywords we have entered and returns the results of the search, providing links to relevant Web sites for us to choose from. Some commonly used search engines are MSN, Alta Vista, Google, Yahoo! search and Info seek etc.