Aromatherapy means "treatment with scent".    It is a branch of herbal medicine that uses essential oils extracted from plants and herbs to treat infections, skin disorders, immune deficiencies and stress.

Incense is aromatic organic materials made from plants and herbs that release a fragrant smoke when burned

Essential Oils are concentrated oils containing volatile aroma compounds from aromatic plants and herbs

Hydrosols is the water that remains after producing an essential oil via steam or water distillation