Speed Metal is not Thrash Metal. Many confuse the two genres. Speed Metal started in the late 70's with bands like Judas Priest and Riot. It's mainly a faster version of traditional heavy metal. while Thrash has a strong hardcore punk influence. I read somewhere someone was saying Megadeth is speed metal. Not True! Speed Metal and Thrash Metal are two completely different genres. While Thrash influenced the more extreme genres, Speed Metal is typically considered more traditional and was around for quite a few years before thrash.

when you're hungover as shit after a spending a night drunk as a skunk

A genre of metal that basically consists of standard heavy metal played at faster tempos with an emphasis on the basic guitar riffs. (Can be compared to a melodic version of thrash.) Created by Judas Priest.

rippingly rapid riffs, mach 9 beats, and a tendency toward thrashing throttle vocals