An essential oil is usually a liquid that has been derived from a plant and distilled. This distilling process usually involves water from a stream or slow-moving river combined with the leaves, flowers, stems, bark and other parts of the plant that is used for making this particular oil. Essential oils do not actually feel oily at all, contrary to the use of the word. Most of essential oils are clear or are a very clear orange or amber color. Essential oils are believed to contain the true essence of the plant or tree from which they were obtained. Due to the high concentration that the essential oils maintain, they are often sold in very small bottles that can last a long time.

Essential oils, while they do represent scents, are not the same or even similar to fragrances or perfumes. Essential oils are always derived from real plants, while the vast majority of perfume or fragrance oils are artificially created or at the very least contain artificial substances and often offer little or no therapeutic value. Since the use of the word aromatherapy is not yet regulated by the United States government, many companies will offer fragrance oils as aromatherapy therapeutic oils even though they are not the same. This is an unfortunate situation as many times these fragrant oils have little or no natural ingredients. It is important to understand that if an aromatherapy product contains any type of synthetic or perfume oil, it is not a true aromatherapy product, simply someone trying to sell a lesser product as a greater one.