An AA battery is a standard size of cylindrical battery commonly used in various electronic devices. It typically measures about 50.5 mm in length and 14.5 mm in diameter. AA batteries can be found in two main types: alkaline and rechargeable nickel-metal hydride (NiMH). They provide a voltage of 1.5 volts for alkaline and 1.2 volts for NiMH. These batteries are widely used in items such as remote controls, flashlights, and toys. Their popularity is due to their versatility and availability, making them a convenient power source for everyday gadgets. Proper disposal and recycling of AA batteries are important to minimize environmental impact.