A wet bar is a small bar used for mixing alcoholic beverages, which differs from a regular bar in that it includes a sink with running water. A wet bar can increase the rate at which drinks are served because of the sink, which allows for glasses to be cleaned immediately. The sink may also be used for adding water to drinks.
Wet bars are found in homes for entertainment purposes. A finished basement is a typical location for a wet bar. Wet bars are relatively simple to build, and, thus, many homeowners have turned the wet bar into a do-it-yourself project. Recently, hotels have been incorporating wet bars into rooms, in which case the customer must pay to use the wet bar per drink. Including a refrigerator beneath the bar or cabinet is a popular option. This is useful for making chilled drinks and preserving previously made mixtures.
Source of the article : Wikipedia