[LinuxBIOS] Silly Question

This is a silly question but, when I see something like this (2<<20)  
in raminit.c it is saying to change bit 20 to a value of 2?? Is that  
correct?? That would have to be a binary value than right? Than what  
would that look like?? Just trying to understand the whole registry  
setting thing better.

Thanks - Joe