I am a technical person and this book provided the indepth discussion of the entire circuit operation of a typical DVD drive sold to consumers. This book is excellent for the savy technical engineering person in need of troubleshooting a DVD drive deck and lacking the manufacturer's technical information, schematics etc. A very good technical book. Would be an excellent book for a technical class. Generous amount of diagrams, pictures and illustrations of signal flow to circuit diagrams to items of hardware.