Ok lets see, we have one person complaining that its to hard becuase you must concentrate, another saying its to mathematical. Well I hate to say it, BUT THAT IS THE POINT of this. Computer graphics isn't like 1+1=2. More along the lines of 4(4(3/4 - 1/2)*4)= X. This book presents everything perfectly. A great recommendaiton for anyone 'who wants to learn it' but if your thinking of just a simple, 21 days or don't have time/concentration, don't get this book. I recommend looking into 'other' subjects.