This document provides an overview of different mediums of communication. It begins with an introduction defining communication and its process. The document then discusses the history of various communication mediums such as the first telephone system in 1876, mail airplanes in 1911, Xerox machines in 1966, and email in 1971. It categorizes mediums of communication into physical and mechanical types and provides details on specific mechanical mediums like telephone, mobile phone, television, fax, radio, and internet. For each medium, it highlights the important people involved in their invention or development.