Different people have different definitions for Goth's. Well this is what wikipedia thinks a goth is, and they are normally right.
The goth subculture is a contemporary subculture found in many countries. It began in the United Kingdom during the early 1980s in the gothic rock scene, an offshoot of the post-punk genre. The goth subculture has survived much longer than others of the same era, and has continued to diversify. Its imagery and cultural proclivities indicate influences from nineteenth century Gothic literature along with horror movies and to a lesser extent, - according to César Fuentes Rodríguez and Carol Siegel - the BDSM culture.
The goth subculture has associated tastes in music, aesthetics, and fashion, whether or not all individuals who share those tastes are in fact members of the goth subculture. Gothic music encompasses a number of different styles. Common to all is a tendency towards a lugubrious, mystical sound and outlook. Styles of dress within the subculture range from deathrock, punk, androgynous, medieval, some Renaissance and Victorian style clothes, or combinations of the above, most often with black attire, makeup and hair.