Final answer:
Fan culture and communities are considered social institutions because they facilitate the creation of strong community bonds within previously secondary groups, particularly through the use of social media, and embody characteristics that are essential to the functioning of such institutions.
Step-by-step explanation:
Fan culture and communities, as they relate to musicians' fanbases and their interactions on social media platforms, illustrate the characteristics of social institutions. These interactions often transform secondary groups into primary groups through the shared experiences and strong community bonds that form online. The reach of social media in the transformation of fan culture and its emergence as a central topic in the study of sociology is evident, particularly when considering how fanbases compare to traditional folkways. Furthermore, fan culture provides a social network, offers emotional support, and encourages individual members to challenge their beliefs, which are all essential aspects of social institutions.