how are alcoholic beverages of alcohol content greater than the optimum concentration obtained ?

An alcoholic beverage is a drink containing the psychoactive drug ethyl alcohol  and small quantities of other alcohols. In Alcoholic beverages, the concentration of ethyl alcohol has been increased above that of the original fermented mixture by a method called distillation. If a liquid containing ethyl alcohol is heated to a temperature between 78.5° C to 100° C and the vapour coming off the liquid is condensed, the condensate will have a higher alcohol concentration.

By convention any beverage with alcohol content greater than 2% is considered an alcoholic beverage.