The Mini-Split is similar to the Traditional Heat Pump, Air Handler system in that it is electric, and can deliver both heating and cooling. The main difference is it is ductless, with the air handler usually wall mounted in the room inside the home that it is focused on serving.
Mini-splits can also be cooling-only if your home already has a heating system (e.g. radiators or a fuel-sourced furnace). Much like a Traditional Heat Pump, Air Handler system it has an outside compressor unit, and an indoor air handler (wall mounted). The outside unit can connect to more than one wall mounted air handler to serve more than one room, if so equipped.
Ductless Mini-Splits are ideal to serve a new addition to your home or even an older home where accommodating traditional sheet metal ducts and/or flex ducts is difficult due to space constraints.