There are many technical books that become thinker and thicker and the pressure from the technical society is more and more to read them and remember many concepts described in them. But it's so hard to do it. I have only a few hour a week to read them and when I reach the middle of the book I forgot most of what I've read at the beginning, because lots of time passed. If I go back, I'll just re-read the same stuff over and over, never going past 50% of the book. So, even after I finished reading a thick tech book I forgot most of it. How do you remember all that stuff? I had a talk in my University on how to do it. They advised to use some cards with basic info so that you can remember the details when you look at it. Do you use such cards or do you have other ideas how to do it?