Completely accessible for anyone with an interest in physics.  Mr Feynman was one of the most important theoretical physicists of the last century and a fantastic communicator.<br>This and "Six Not So Easy Pieces" are a pleasure also for students of physics.  Highly recommend also "Surely You Are Joking, Mr Feymnan" and "What Do You Care What Other People Think" for any reader.<br>Read all of his books that you can.