Silly question - how do I understand the cut list?

Hi there,

Finally, after several false starts, am about to choose between the binder of saved plans and get working!  However I can understand what I need to buy... I think... but then get confused at the cut list.  Is there a post that explains or walks through something that basic?  For example, I'm looking at the play sink:

First cutting instruction is that I'll need two 20" pieces cut from a 1x12... is that right?  Have I interpreted that correctly?

Thanks! 

Neala