genre rests around a relationship between similarities and differences

What is Genre:

– A style or category of art, music, or literature.

It helps identify how media texts are classified, organised and understood, essentially around SIMILARITIES and DIFFERENCE. Media texts hold similar patterns, codes and conventions that are both PREDICTABLE and EXPECTED, but are also INNOVATIVE (different) and UNEXPECTED.

Genre is a way of thinking about media production (INSTITUTIONS) and media reception (AUDIENCES). 

. . . saddled with conventions and stereotypes, formulas and
clichés and all of these limitations were codified in specific genres. This was the very foundation of the studio system and audiences love genre pictures . . .Scorcese, A personal Journey through American Cinema (1995)

Genre is important for institutions and audiences as they become recognisable by their own styles.

Scorcese, A personal Journey through American Cinema (1995)

. . . saddled with conventions and stereotypes, formulas and
clichés and all of these limitations were codified in specific genres. This was the very foundation of the studio system and audiences love genre pictures . . .Scorcese, A personal Journey through American Cinema (1995)