HVDC technology is being used to connect two systems with different frequencies (back to back) and long distance bulk transfer of electrical power due to low losses, no reactive power requirement and virtually no limit to the transmission distance. This book presents various aspects of HVDC to a beginner and focuses on 1) high voltage DC power transmission that includes overhead cables, underground DC cables and submarine cables 2) high voltage circuit breakers that include oil, vacuum, air and SF6 circuit breakers 3) high voltage DC circuit breaker: proposal, simulation and analysis 4) electromagnetic interference caused by HVDC power transmission The book should be of interest to the electrical engineering students and graduates, researchers and high voltage engineers involved in power transmission.