Vermouth is fortified, or "aromatized", wine, where botanicals (such as roots, tree bark, spices or seeds) are added to the wine. Traditionally vermouth was used for medicinal purposes, to treat various ailments, but it became popular as an aperitif to be enjoyed before meals, or in cafes at any time of the day.
Modern vermouth was first produced in the 18th century, in Turin, Italy, although fortified wines have been produced and consumed throughout history. Today it is enjoyed either straight or in classic cocktails such as the Negroni, the Martini, or the Manhattan. To make vermouth, a manufacturer starts with basic grape wine or unfermentend wine must, and then adds additional alcohol and a unique blend of aromatic elements. It is finished with the addition of sugar (either pure cane or caramelized).
The two main types of vermouth are sweet or dry. However today there are many variations available to suit one's tastes: extra-dry white, rose, amber, sweet white...it's your choice! Vermouth is still primarily popular in Italy and France, but there are manufacturers in other countries now trying to come up with their own unique vermouth style.