Question about guitar Gear

[epicmoee]

I love metal, but my knowledge about guitars is close to zero. This is probably a dumb question, but please help...
http://www.youtube.com/watch?v=mnICreH1mCk&feature=plcp

I was watching the above video and I noticed that he had some kind of stick-ish thing on the guitar and he twisted it up, (like at 0:27) which seemed to cause some kind of distortion. What is it called? Is it attached to the guitar? Or is it something sold separately?
(Sorry if this is stupid. I don't know much about playing guitar)

Please help!!!

[Algonquin]

Not a supid question Moe... have a look here...

http://www.youtube.com/watch?v=wUu9I-xfUsQ

[Alex2100]

Hi friends i just love to play the guitar and this is also my favorite hobby to play guitar and become a guitarist in my life because this is a good passion and also have so9 many fans anyways i have a question about guitar that i want to add string in my guitar so where to get this string...???

Emcee in Singapore (http://emceemelvin.com/emcee-videos/)