[1] The genre categorizes a piece based on a shared tradition or an overarching set of conventions, like opera or symphony.
A notable source of confusion is the term 'sonata': as a genre, it denotes a multi-movement composition for one or more solo instruments, while in structural terms, 'sonata form' refers to a specific three-part structure (exposition, development, recapitulation) frequently used within individual movements of larger works.
Historically, genres emerged from a fusion of social functions and compositional conventions and served as communicative tools that guided listeners' experiences and responses.
[2] Because genres are defined not only by their musical elements but also by social contexts, functions, and validation by specific communities, their definitions are subject to change as these validating communities evolve even if the musical notes themselves remain unchanged.
[2] In summary, genre is a broader term and often refers to the overall style, structure, cultural context, or purpose of the music.