Mathcore is a subgenre of heavy metal that combines elements of hardcore punk and progressive metal. It is characterized by complex time signatures, dissonant chords, and abrupt tempo changes, creating a chaotic yet intricate sound. Bands often use unconventional song structures, making the music unpredictable and challenging to follow. The genre emerged in the late 1980s and early 1990s, with bands like The Dillinger Escape Plan and Converge leading the way. Mathcore often features aggressive vocals, intricate guitar work, and intense drumming, appealing to listeners who enjoy technical musicianship and experimental approaches to music.