Both are split systems in the sense that the condenser is outside and the air handler is inside. A traditional split system uses ductwork to distribute conditioned air throughout the space, while a ductless mini-split delivers air directly into the room through a wall-mounted air handler, no ducts required. For spaces with existing ductwork, a ducted split system is typically the right choice. For spaces without ducts, a ductless mini-split is the more practical option. Interstate installs both.