Instruct: Classify Amazon reviews into positive or negative sentiment
Query: An excellent book for everyone

I have been working with RF and Electromagnetics for a few years and still I think that this book was great reading for me. It is not for those who are satisfied if things are working and they already know the basics, rather it is for those who want to know WHY things happen. I bet most active RF designers would have hard time explaining why all the high frequency tricks are needed and at which frequency these should be used. This book answered many of my simple and 'stupid' questions.