[newbie] Screens 1,2,3 and 4

[cosmorph]

I have a question. 
Sometimes when you initialize programs the programs window 
goes beyond the edge of your screen. When I first started messing 
around with linux I pressed a button that enabled me to move 
around on the entire desktop screens 1,2,3 and 4 by just moving 
my mouse icon to the edge of the screen. If anyone knows which 
button that is, Id greatly appreciate it?
 
Jerome
[EMAIL PROTECTED]