Vermouth (also spelled vermuth) is a fortified wine flavored with aromatic herbs and spices ("aromatized" in the trade) using closely-guarded recipes (trade secrets). Some vermouth is sweetened; however, unsweetened, or dry, vermouth tends to be bitter. The person credited with the first vermouth recipe, Antonio Benedetto Carpano from Turin, Italy, chose to name his concoction "vermouth" in 1786 because he was inspired by a German wine flavored with wormwood, a herb most famously used in distilling absinthe. The modern German word Wermut (Wermuth in the spelling of Carpano's time) means both wormwood and vermouth. The herbs were originally used to mask raw flavors of cheaper wines, imparting a slightly medicinal "tonic" flavor.
There are three general styles of vermouth, in order from driest to sweetest: extra dry, bianco/white, and sweet/red. Sweet red vermouth is drunk as an apéritif, often straight up, as well as in mixed drinks like the Manhattan. Dry white vermouth, along with gin, is a key ingredient in the mixing of martinis. Red vermouths are sometimes referred to as Italian vermouths and white vermouths as French vermouths, although not all Italian vermouths are red and not all white vermouths are French.