Volume 2 of the book begins with chapter 6, in which we have taken up conventional MWTs (such as TWTs, klystrons, including multi-cavity and multi-beam klystrons, klystron variants including reflex klystron, IOT, EIK, EIO and twystron, and crossed-field tubes, namely, magnetron, CFA and carcinotron). In chapter 7, we have taken up fast-wave tubes (such as gyrotron, gyro-BWO, gyro-klystron, gyro-TWT, CARM, SWCA, hybrid gyro-tubes and peniotron). In chapter 8, we discuss vacuum microelectronic tubes (such as klystrino module, THz gyrotron and clinotron BWO); plasma-assisted tubes (such as PWT, plasma-filled TWT, BWO, including PASOTRON, and gyrotron); and HPM (high power microwave) tubes (such as relativistic TWT, relativistic BWO, RELTRON (variant of relativistic klystron), relativistic magnetron, high power Cerenkov tubes including SWO, RDG or orotron, MWCG and MWDG, bremsstrahlung radiation type tube, namely, vircator, and M-type tube MILO). In Chapter 9, we provide handy information about the frequency and power ranges of common MWTs, although more such information is provided at relevant places in the rest of the book as and where necessary. Chapter 10 is an epilogue that sums up the authors' attempt to bring out the various aspects of the basics of and trends in high power MWTs.