Computer Science Class 11 Chapter 2 Notes

• What are Information / Computer Networks? OR Define Information / Computer Networks?
• Define or Describe Workgroup Computing.
• Define E-mail and Describe its Benefits. OR What are Benefits of E-mail ?
• What are Benefits of E-mail.
• Define Internet and Describe its History.
• Internet : [The Internet is a huge network of connected computers that provide us a facility of exchanging data, messages, and files with other computers that are connected to the Internet]. Internet has brought the world nations to the realization of a “Global Village”, in which we feel, everyone as close as our neighbor. History or The Birth of Internet. During late l960s, it was designed as ARPANET (Advanced Research Project Agency NETwork) by the US Department of Defense - DARPA, in collaboration with other universities and research organizations. In the beginning, ARPANET was used mainly for communication technology research and development, with scientists at various sites connected through a network, to share the information. Later, throughout l970s and 1980s, ARPANET evolved into several other networks dedicated mostly to military use. In 1989, all the previous networks, created for military use, were abandoned and replaced by National Science Foundation’s NSFNET. The Internet has grown rapidly since 1990. According to the Internet Society (the monitoring organization), the number of computer networks in the Internet is more than Two Million and the number of computers that connect to these networks is more than Hundred Million.
• How and where was Internet Born.
• Define or Describe or Explain Components of Internet.
• Define or Describe Components of Network.
• Define or Describe LAN’s Protocol? List commonly used Protocols.
• Explain LAN, WAN and MAN.
• Explain the Concept of a Network.
• Describe Uses of Network.
• Explain Network Models.
• Explain Network Standards.
• Explain Network Topologies.
• Define Open Systems Interconnection(OSI)Model and Explain it layers. 
• Workgroup computing is highly important aspect of modern world computing in today's business, academic, technological and research oriented atmosphere. It is also known as collaborative computing and it enables the individuals and teams of certain projects to use computer networks for the purpose of cooperation, consultation, and information sharing. With the help of groupware, many users or researchers can work on their projects by sharing the same domain of information online. It also permits the individuals to collaborate with their colleagues to work on company information over the network. At the same time, they can also link to other important contacts outside their organization.
• The information may reside on heterogeneous type of databases, it may be made available using altogether different operating systems, and it may be using different platforms. But as long as the users are communicating with each other through a common shareware and they belong to same group, they will keep on working without any hassles and problems. In fact, it is the smart service of communication technology that has brought about a revolution in this type of computing. The concept of "global village" has become a reality now and the computer community are sitting face to face.