Discussion of perception in individuals
Perception is, on a basic level, the process of both receiving and interpreting factual knowledge. Whether it refers directly to sensory data or knowledge passed on to an individual from some indirect source such as the media, perception involves both the act of receiving the information and the implication that one's individual bias has likely colored the resulting conclusions.
Discussion of perception in society
There are two ways in which one can discuss the concept of perception on a collective level. The first dynamic is the consideration of the transmission and reception of ideas on a group level, and the bias which a group as a whole uses as a lens through which to view facts. The second paradigm through which to discuss the issue is as an accumulation of individual perceptions, and the ways in which the individual perceptions interact to form a group mindset.
How it currently works
In our current situation, most people interpret factual information through a series of lenses. Individuals receive information from secondary sources such as mass media outlets, whom already passed the factual data through individual and group perception, and then the individuals take this post-perception information and pass it through their own perception process.