Short answers, pulled from the story.
Plato excluded lyric poetry from his original classification of literature, labeling it a non-mimetic mode that did not fit his rigid three-part system of dramatic dialogue, pure narrative, and epic.
Aristotle revised the framework by eliminating the pure narrative mode and introducing two new criteria to distinguish genres: the object to be imitated, which could be superior or inferior, and the medium of presentation, such as words, gestures, or verse.
The hierarchy of genres in France between the 17th and 19th centuries placed history painting at the top and still life and animal painting at the bottom, with idealism privileged over realism in line with Renaissance Neo-Platonist philosophy.
Carolyn Miller defines genres as types of actions rather than types or forms of texts, reasoning that recurring rhetorical problems tend to elicit recurring responses that become typified or socially constructed as recognizable types.
Genre painting is a term for paintings where the main subject features human figures to whom no specific identity attaches, while staffage refers to incidental figures in what is primarily a landscape or architectural painting.
The term microgenre came into usage in the 21st century, most commonly referring to music and associated with the hyper-specific categories used in recommendations for television shows and movies on digital streaming platforms such as Netflix.