This book provides comprehensive coverage of the basic theoretical work required by Marine Engineering Officers and Electrotechnical Officers (ETOs), putting into place key fundamental building blocks and topics in electrotechnology before progressing to more complex topics and electromagnetic systems. Volume 6 covers essential basic electrotechnology principles for the 21st century, including the fundamentals of electron theory, AC and DC current, circuits, electromagnetism and electrochemistry, providing a firm foundation for complementary Volume 7 in the Marine Engineering Series to discuss emergent technology such as image intensifers, the transistor, increased maritime use of LEDs, and references to modern ship systems such as GPS, ECDIS, Radar and AIS. This new edition has been thoroughly updated in line with guidelines, best practice and the many technological developments that have taken place over the past 5 years since the previous edition published, as well as improvements and updates to the technical diagrams.