If we think of the long history of life on earth as one day, ther mass communication has come into existence only in the last second before midnight.
Animals communicated with each other for millions of years before any of them developed language. Human animals spoke to each other in common languages for hundreds of thousands of years before any of them learned to write. Knowledge and ideas were shared and preserved in writing for thousands of years before there were mass media.
Thus, when we speak of mass communication we are really referring only to the five hundred years since it became possible to print from movable metal type in the fifteenth century. The rate of development has been truly extraordinary. From language to writing: hundreds of thousands of years. From writing to printing: thousands of years. From printing to films and broadcasting: four hundred years. From the first experiments with television to live television from the moon: forty years!
Technically, what has happened in the last five centuries is that man has developed some remarkable machines that can be inserted into the communication process to duplicate a message almost without limit, and to extend almost indefinitely a person's ability to see and hear and record, and thus to share, information. The communication process remains basically the same. The psychology of communication is basically the same as you have read about in other chapters of this book. But because man lives by information, this new ability to share it,