The term AEG comes from: Airsoft Electric Gun. This is the most well known types of airsoft gun in the world. They have very good accuracy and come in many different types of models. Using a battery, it powers a gearbox (internal air compressor) to propulse the bbs out of the barrel. Low maintenance, many upgradable parts and good reliability are some of the key features. The best choice for any new to expert player.