What is aroma therapy if so which is the best aroma?

Aromatherapy. Aromatherapy is the use of essential oils -- concentrated extracts of leaves, roots, seeds, or blossoms -- from plants for healing. They're usually diluted into a carrier oil, and can be inhaled or massaged into the skin. Sometimes they're placed in diffusers and spread into the air in a room. Oils are chosen according to desired effect. Lavender = relaxing. More: http://tinyurl.Com/psv9n22.
Aromatherapy. It depends on what you want to address. Citrus is invigorating. Lavender is calming. Vanilla and cinnamon are sexually arousing.