Essential oils are concentrated hydrophobic liquids containing volatile chemical compounds from plants. They are also known as volatile oils, ethereal oils, aetheroleum, or simply as the oil of the plant from which they were extracted. Essential oils are essential in the sense that they contain the essence of the plants fragrance—the characteristic fragrance of the plant from which it is derived. The term "essential" used here does not mean indispensable or usable by the human body, as with the terms essential amino acid or essential fatty acid, which are so called because they are nutritionally required by a living organism.
Essential oils are generally extracted by distillation, often by using steam. Other processes include expression, solvent extraction, sfumatura, absolute oil extraction, resin tapping, wax embedding, and cold pressing. Essential oils are often used in aromatherapy, a form of alternative medicine that employs plant extracts to support health and well-being. Some of the health claims associated with essential oils are controversial, but they can make a positive impact on health and well-being as long as they are used in a safe way. The benefits of essential oils depend on the type of oil, but some popular ones include lavender oil, tea tree oil, frankincense oil, peppermint oil, eucalyptus oil, lemon oil, lemongrass oil, and orange oil.
