post-hardcore

A genre combining the artsy sensibilities of post-punk with the general energy of hardcore punk. Vocals can vary wildly, from cleans to screams to even death growls (do keep in mind that death growls aren't really part of the original scene). Later on, many post-hardcore bands would add influences from pop punk, metalcore or even melodic death metal.

Several genres would evolve from post-hardcore over time, such as emo and it's derivatives such as screamo and emo-pop, or mathcore, which is a combination of math rock and post-hardcore. Many melodic metalcore bands also have post-hardcore sensibilities.

Also, the best genre known to man

Original bands: Nomeansno, Fugazi, At the Drive-In, Minutemen
Modern post-hardcore: The Used, The Fall of Troy (notable for probably being the most ATDI influenced modern post-hxc act), Thrice, Saosin, Aiden
Metalcore/post-hardcore hybrids: Poison the Well, Glassjaw, Thrice (their older material), Alesana, Atreyu, 36 Crazyfists, Nothingface (notable for being one of the most post-hxc and metalcore infused early nu metal acts), Escape the Fate, The Dillinger Escape Plan, Botch, Enter Shikari (notable for being the first trancecore band)