Since digital photography became the norm I have used most of the software packages available. Each of these has had a steep learning curve and necessitated buying the supportive books or manuals.
The vast majority of these have left me more confused than I was before.
Apple Aperture 2; A workflow guide is completely different. In language that even I can understand the text carries you through the advantages of RAW files and a sequence of actions in addressing them that makes complete sense.
I cannot recommend this work highly enough.