What are essential oils?:
From the Merriam-Webster dictionary, essential oils are defined as:
an oil that comes from a plant, that smells like the plant it comes from, and that is used in perfumes and flavorings
Essential oils are volatile compounds that quickly disperse throughout the medium they are used in. They are the basic component of most air fresheners, colognes and perfumes, and are very useful in baking. They are normally produced by extracting and concentrating the oils of various plants. Almost every plant has an oil component which can be extracted. As I said, some of these, such as peppermint oil, are useful in cooking and baking as they greatly enhance the flavor of the item. They a large part of any sort of odor based item you use everyday, and they are the major component of aromatherapy.