Most people think that your brain can only hold a small amount of limited information. But this actually couldn’t be further from the truth. According to Dr. Paul Reber, the director of the Brain, Behavior, and Cognition program at Northwestern University, the brain does have a limit, but it’s far beyond anyone’s reach: somewhere in the vicinity of a million gigabytes. Just to put this into perspective, if you had a DVR with that kind of capacity, you could store three million hours of TV shows, or a little more than 342 years of nonstop action. Or if you wanted, you could memorize word for word every how-to book on the planet, and still have room left over for a lot more.

I don’t necessarily recommend doing that, but I do like your suggestion of optimizing your retention by focusing on information that improves yourself and others.