Networking in computer is a part of computer engineering. It is studying and analyzing the communication process of various devices and systems that are connected or linked for the purpose of communication. It deals with sharing or exchanging resources while communicating.
Computer networking or otherwise called data networking is digital communication network which allows nodes to share information. Computing devices like computers, routers, satellites, servers exchange data for communication. The medium for exchanging data is done through cable media like wires or optic cables or wireless media like Wi-Fi.
The computer devices that produce, route or transmit and terminate data is called network nodes. The hosts of this nodes are our computing devices like Personal computers, laptops, mobile phones and any device which is communicating either way. If there is exchange of nodes between 2 devices we can say that they are networked together.
Without network the communication taking place between YOU and I may not be possible. Internet is solely based on networking only.