This lecture focus to describe on introduction to Computer Networks. Here briefly explain uses of Computer Networks: Business Applications, Home Applications, Mobile Users, Social Issues etc. Network Hardware: Local Area Networks, Metropolitan Area Networks, Wide Area Networks, Wireless Networks, Home Networks, Internetworks etc. Network Software: Protocol Hierarchies, Design Issues for the Layers, Service Primitives etc. Finally explain on Architecture of the Internet, ATM Virtual Circuits, Ethernet and Network Standardization.