NiMH, or Nickel-Metal Hydride, is a type of rechargeable battery commonly used in various electronic devices. It consists of a nickel oxide hydroxide positive electrode and a hydrogen-absorbing alloy negative electrode. NiMH batteries are known for their higher capacity compared to traditional NiCd (Nickel-Cadmium) batteries, making them suitable for applications like digital cameras and hybrid vehicles. One of the key advantages of NiMH batteries is their ability to hold a charge longer and provide more energy per weight than older battery technologies. They are also more environmentally friendly than NiCd batteries, as they do not contain toxic cadmium. However, they can self-discharge more quickly when not in use.