Essential oils or "essences" are highly volatile oils extracted from aromatic plants. The chemical make-up of essential oil is very complex. They have a "micro-sized droplet and molecular structure that allows them to be absorbed into the bloodstreams by inhalation and trans-dermal applications. Essential oils are legendary for their antimicrobial properties. In addition to the medicinal properties attributed to essential oils, they are legendary for uplifting the emotions. The dynamic effects of essential oil aromatherapy on the emotions has resulted in the practice of "psychoneuroimmunology." The relatively new science of psychoneuroimmunology has reported that pleasure producing experiences (i.e.-love, music, massage, fragrances) will in fact enhance the human system.