Short answers, pulled from the story.
A microgenre is a narrowly defined subcategory within music, literature, film or art, often used to describe a specific stylistic offshoot of a larger genre. The term has been used since at least the 1970s, especially to describe sub-subgenres of heavy metal and electronic music.
The term "microgenre" was coined in a 1975 French article about historical fiction, alongside the related term "macrogenre." Its author defined a microgenre as "a narrowly defined group of texts connected in time and space."
By the late 2000s and early 2010s, online platforms let microgenres emerge and spread rapidly, often tied to internet aesthetics and trends. Notable internet-based music microgenres include chillwave, witch house, seapunk, shitgaze, dreampunk and vaporwave.
Glenn McDonald, formerly of the Echo Nest, built genre-mapping data in 2013 that became part of Spotify features like "Daily Mix" and "Fans Also Like." He added the term "hyperpop" to Spotify's algorithm in 2018, and in August 2019 a Hyperpop playlist curated by Lizzie Szabo helped popularize the movement.
In 2020, Netflix identified 76,897 different film microgenres within its recommendation algorithms. Netflix used categorizations like these to help develop series such as House of Cards and Orange Is the New Black.
Critics such as Grantland's Dave Schilling argued that the chillwave label revealed how arbitrary such names can be, calling it "a parody of a scene" rather than a real one. PopMatters' Thomas Britt warned that bands tailoring themselves to a microgenre tie their fortunes to that category's shelf life.