Interactive electronic book operating systems and methods for displaying and allowing customization of content of scientific, engineering and other technical and professional digital books. The display screen can include icons for forward and backward page turning, generating of dynamic indexing and tables of contents, bookmarking, color themes, floating pages, highlighting, adding sticky notes, hiding selected content on the pages, quizzing the reader, lecturing the reader, tutoring the reader, showing the reader additional designs and practical relevance, and allowing the instructor to generate uniform seed numbers for problems and designs and/or allowing the instructor to generate random seed values for problems and designs.