Music is very difficult to define, but here are some loose definitions.
Ska: A form of Jamaican music with Rhythm & Blues. The rhythm accents are on the upbeats. There is usually a strong brass horn element. Some musical artists are: Laurel Aitken (known as "The Godfather Of Ska"), Toots & the Maytals, The Beat (aka The English Beat in the US), The Specials, Madness, Reel Big Fish, and Catch 22.
Jazz: A big band dance music native to America with stong rhythm and swing, improvisation. Some musical artists are: Charlie Parker, Dizzy Gillespie, Count Basie, Miles Davis, Lionel Hampton, and Kenny G.
Reggae, Hip-Hop, Math Rock, Country, Classical, Classic Rock, Punk, Ska Punk, ...