The answer to 'ductless system or ductless system' is that they are the same thing. A ductless HVAC system, also known as a mini-split system, is an air conditioning and heating solution that does not require the extensive ductwork of a traditional central HVAC system. These systems consist of an outdoor compressor/condenser unit and one or more indoor air-handling units connected by refrigerant lines.
Ductless systems offer several benefits over traditional ducted systems, including improved energy efficiency, zoned climate control, easy installation, and greater flexibility in placement. They are a popular choice for homes or additions without existing ductwork, as well as for spaces like garages, attics, or bonus rooms where installing ductwork would be difficult or expensive.