Drink coaster

A coaster, drink coaster, beverage coaster, or beermat is an object used to rest drinks upon. Coasters protect the surface of a table, or any other surface where a user might place a cup, from condensation created by cold drinks. A coaster on top of a beverage can also be used to show that a drink is not finished or to prevent contamination (usually from insects). Coasters can also stop hot drinks from burning the table surface.

In a pub or bar, coasters are used to protect tables and bar surfaces. Coasters are typically made of paper, and sometimes are used to write on. Coasters are often branded with trademarks or alcohol advertising. Coasters are not to be confused with bar mats, which are larger pieces of rubber or absorbent material that are used to protect countertops or floors and to limit the spread of spilled drinks.