Well, there are different kinds of Networking as mentioned below but which Networking that you are asking for?
Dial-up networking
Home networking
Computer networking
Virtual private networking
Client-server networking etc. etc.
Presuming the question is about a Computer networking the answer is given below.
Network occurs any time you connect two or more computers together so that they can share resources. Networking consists of software/hardware in combination systematically linking a number of devices (computers, workstations, printers) into a network (system) for the purpose of sharing resources.
Computer networking is the engineering discipline concerned with communication between computer systems or devices. Networking, routers, routing protocols, and networking over the public Internet.
Communicating computer systems constitute a computer network and these networks generally involve at least two devices capable of being networked with at least one usually being a computer. The devices can be separated by a few meters (e.g. via Bluetooth) or nearly unlimited distances (e.g. via the Internet). Computer networking is sometimes considered a sub-discipline of telecommunications, and sometimes of computer science, information technology and computer engineering. Computer networks rely heavily upon the theoretical and practical application of these scientific and engineering disciplines.
A computer network is any set of computers or devices connected to each other. Examples of networks are the Internet, or a small home local area network (LAN) with two computers connected with standard networking cables connecting to a network interface card in each computer. All modern aspects of the Public Switched Telephone Network (PSTN) are computer-controlled, and telephony increasingly runs over the Internet Protocol, although not necessarily the public Internet.