BLACK + DECKER has 3 different battery platforms, namely the 18V, the 36V, and the 54V battery system. This means that if you buy tools with battery and charger, you also use the battery for another Black Decker device with the same battery system. Suppose you bought a lawn mower where you get a battery from the Black and Decker 18V battery system, you can also use the same battery on your Black & Decker 18V drill with the same voltage and the same battery platform. This way, you don't have to buy a new battery unnecessarily for every new machine. The biggest advantage of cordless tools is cordless freedom. This eliminates the hassle of cords getting in the way and you don't have to look for a socket.