The answer to 'difference between air conditioner and' is that an air conditioner is a system that cools and dehumidifies the air in a home or building, while a heater is a system that warms the air. Air conditioners use refrigeration to remove heat and moisture from the air, while heaters use a fuel source like electricity, gas, or oil to generate heat.
Air conditioners are typically used in the summer to keep a home or building cool and comfortable, while heaters are used in the winter to provide warmth. Air conditioners also have the added benefit of reducing humidity levels, which can make the air feel more comfortable. Heaters, on the other hand, are focused solely on heating the air and do not provide dehumidification.