Cultural diffusion refers to the spread of traits from one person or place to another. This is how cultural traits that originally belong to a particular area can be popularized somewhere else. This can occur with beliefs, technology, traditions, language, etc. A particular type of diffusion is contagious diffusion. This refers to a system by which diffusion is spread to a large number of people with no particular rule or system. Contagious diffusion also spreads o a way that does not recognize borders as it spreads. An example of this are images shared over social media.
The fourth type of cultural diffusion. similar to expansive diffusion except that it involes a rapid and invasive diffusion of trait through the culture group. it is termed contagious disease is spread.
