“Fandom (a portmanteau of fan [fanatic] and the suffix -dom [domain], as in kingdom, freedom, etc.) is a term used to refer to a subculture composed of fans characterized by a feeling of sympathy and camaraderie with others who share a common interest. Fans typically are interested in even minor details of the object(s) of their fandom and spend a significant portion of their time and energy involved with their interest, often as a part of a social network with particular practices (a fandom); this is what differentiates “fannish” (fandom-affiliated) fans from those with only a casual interest.
A fandom can grow up centered around any area of human interest or activity. The subject of fan interest can be narrowly defined, focused on something like an individual celebrity, or more widely defined, encompassing entire hobbies, genres or fashions. While it is now used to apply to groups of people fascinated with any subject, the term has its roots in those with an enthusiastic appreciation for sports.”
Fans have become important to work in media sociology and cultural studies for a variety of reasons: they can be taken to represent a dedicated, active audience; they are consumers who are often also media producers; and they can be analyzed as a significant part of contemporary consumer culture.
In my opinion, the Internet has helped greatly in the Fan culture. We can see, many people have many fans in facebook and twitter, whether politicians, celebrities, singers or writers.
Different fans have different cultural, for example, football fans, the fans of each team has its own spirit of a cultural, favorite colors, team song and so on.
About Fan activity as a remix, I would say this activity contribute to the culture, a film called The Avengers, it can mix different fans together, It help to share different Fans culture.