A cocktail is otherwise known as a mixed drink because it consists usually of stirring or shaking two or more liquors together plus other ingredients. Before cocktails were being made, most people drank straight liquor. If you watch westerns, the gunslingers go to the saloon. They will usually ask for whiskey or another liquor. The bartender just pours the alcohol straight into a glass.
It wasn’t until the 1870s and 1880s that bartenders starting learning how to mix liquors together along with other ingredients to make these mixed drinks. Most likely, the first cocktail or mixed drink may have been an Old-fashioned or a drink made with whiskey and a few other liquors. There were probably about four ingredients in this first drink.