A HEV, or Hybrid Electric Vehicle, is a type of vehicle that combines an internal combustion engine with an electric motor. Unlike plug-in hybrids, HEVs cannot be charged from an external power source; instead, they generate electricity through regenerative braking and the internal combustion engine. This allows HEVs to use electric power at low speeds and during acceleration, improving fuel efficiency and reducing emissions compared to traditional gasoline or diesel vehicles. HEVs provide a seamless driving experience, automatically switching between the engine and electric motor as needed, making them a practical option for those looking for better fuel economy without the need for charging infrastructure.