AbstractHybrid and plug‐in hybrid electric vehicles are vehicles that combine the use of both petroleum fuels and electricity as their energy sources to propel vehicles and power accessory systems. In general, they are more fuel efficient and environment friendly than conventional petroleum‐powered vehicles in the same class, while being more financially accessible and technically established than pure electric vehicles; thus, hybrid and plug‐in hybrid electric vehicles serve as significant players in the progress of vehicle electrifying transition and result in remarkable market influence in the automotive industry. This article introduces the fundamental concepts of hybrid electric vehicles and plug‐in hybrid electric vehicles, respectively. It gives an overview of the hybrid technologies, current development, benefits, and advantages that these two hybrids have achieved. Different categories and configurations are specified in each type in detail, while diverse operation modes and control strategies are analyzed and illustrated. In addition, parallel comparisons between hybrid electric vehicles, plug‐in hybrid electric vehicles, conventional vehicles, and electric vehicles are made throughout the article in terms of their similarities and differences. Also, the challenges surrounding the future development of hybrid and plug‐in hybrid electric vehicles are discussed at the end of the article.
