Music - whatcha call it

[phantasm]

Some songs have an amazing little piece, that catches your attention, and will pretty much be a perfect sound forever. I'm sure they were probably discovered by some guy just screwing around with an instrument. Is there a name for little pieces of music like this that are only a few notes long but are complete perfection? Here are some examples (you will know which part of the song I am talking about instantly):

http://www.youtube.com/watch?v=BWdLt3Afjrg
http://www.youtube.com/watch?v=bopEpw66_AY
http://www.youtube.com/watch?v=KuMW3l1FCVY
http://www.youtube.com/watch?v=Wod-MudLNPA
http://www.youtube.com/watch?v=Zx3m4e45bTo
http://www.youtube.com/watch?v=tbkG6Za6w5s
http://www.youtube.com/watch?v=W5XRBjsbLPo
http://www.youtube.com/watch?v=HJEySrDerj0
http://www.youtube.com/watch?v=yammJn1vaVg
http://www.youtube.com/watch?v=YIwUxq0BMSE


Wow music, you win tonight.

[thefarmer]

It's called the "Intro", or sometimes the 'the Hook', if it's repetitive.