i've been playing guitar for almost 2 yrs. now, and have a question re: tremolo picking. what does this mean? is it with a whammy bar? or some other device?

and also, if anyone knows about the song "sober" by tool, there's the part where it's quiet after a solo, i think, and then there's a loud screech from a guitar. How do you get that effect?

[This message has been edited by iamthe_eggman (edited 05-10-2000).]