In aromatherapy massage, essential oils are mixed with a carrier oil like sweet almond, apricot kernel, or grapeseed oil. The massage therapist use up to five oils in a mixture, and chooses the oils based on what you need. A relaxing aromatherapy massage, for instance, might have lavender or bergamot, while a massage for sore muscles might include peppermint and eucalyptus.
Essential oils are a volatile, highly concentrated plant extracts, derived from leaves, bark, roots, seeds resins and flowers. They can also be used in hydrotherapy baths, facials and body treatments. You can also use them at home.
Aromatherapy should not be confused with fragrances or perfume oils. Fragrances are often made from chemicals, and lack the therapuetic properties of essential oils. So just because someone lights a scented candle doesn't make it aromatherapy!