Networking and Internet

• A "Network" is a set of computers that interconnect with each other using transmission media. All the interconnected computers must follow a set of communication rules for transmitting and receiving data. These rules are called "Protocols". Networking allows the user to exchange information, share resources, and protect information.
• A Network is classified into 3 types :

  • Local Area Network (LAN)
  • Metropolitan Area Network (MAN)
  • Wide Area Network (WAN)

  1. Local Area Network (LAN) - A local area network is a group of computers that are interconnected in a small area like a building or a campus.

  - Fast data transfer

  - Area covered is limited

  2. Metropolitan Area Network (MAN) - It is a medium-sized network that is smaller than WAN and bigger than LAN. Examples are cable networks, pager systems, etc.
• 3. Wide Area Network (WAN) - A network that connects multiple LANs together. As the name itself implies the coverage area is very wide.

  • The area covered is very big
  • Data transfer is slow compared to LAN.
• Client Server Configuration : In this network, a master PC is called a "Server" which controls and provides services to the users. The user communicates with the PC by sharing resources, accessing programs, etc. The Server has highest operating speed, large memory, and a big hard disk drive. The user acts as a "Client" to the server. Hence, it is known as Client Server Configuration.
• Peer-to-Peer Configuration: In this network, the devices are connected directly to each other since there is no client-to-server relation.
• E-mail:

  E-mail is an Electronic Mail. The messages can be sent electronically over the Internet. For sending and receiving emails, the user must have an email address. The format of an email address is:

  - username@location

  • Username - Name of the recipient
  • @ - It is a character used to separate the username and the location
  • Location - A place, where the email has to be delivered or stored.

  The user can send text, video, files, pictures, etc as an attachment.
• E-commerce: The buying and selling of goods and services over the Internet. E-commerce is known as Electronic Commerce. Websites are created to perform business transactions. Online trading is an important feature nowadays.
• Chat: A form of communication that uses text, audio, and video to communicate with others, even to distant places. The cost of the telephone is very high, but by using this program people can talk to anybody anywhere in the world. Websites having chat programs allow the user to log in to a chat room; and get access to a particular chat room according to your interests. People decide at a particular time and log into the Internet a start chatting.