I still don't know what root beer is.
There are hundreds of root beer brands in the United States, produced in every U.S. state. It is a flavor almost exclusive to North America, yet there are a few brands from other nations around the world, such as the UK, the Philippines, and Thailand where the flavor often varies considerably from the typical North American drink.[1] There is no standardized recipe. The primary ingredient, artificial sassafras flavoring, is complemented with other flavors. Common flavorings are vanilla, wintergreen, cherry tree bark, licorice root, sarsaparilla root, nutmeg, acacia, anise, molasses, cinnamon, clove, and honey.
Although most mainstream brands are caffeine-free, there are some brands and varieties that contain caffeine.[2]
Homemade root beer is usually made from concentrate,[3] though it can also be made from actual herbs and roots. Root beers have a thick and foamy head when poured, often enhanced by the addition of yucca extract. The flavor varies widely between brands and methods--from insipid and insignificant to a bold, rambunctious brew which lingers in the back of the throat and pleasantly makes itself manifest even in the nasal passageways, a hallmark of only the rootiest root beers. The discontinuation of the use of sassafrass root is thought by some to make the difference here.