What , if any, is the difference between rap and hip hop/trip hop music ?

[Iota]

Forgot the artists. Since I assume you're familiar with the classics and big shots in the biz I'll stick to some 'lesser known' artists.

Madvillain
Aesop Rock
Why?
Cyne
Nujabes
Gonjasufi
Saul Williams
Modill
Dälek
Move.meant
Eyedea & Abilities
Castheadwork
...