Coasters

Coasters are small flat mats placed under cups or glasses to protect underlying surfaces from heat, moisture, and condensation. They are widely used in homes, offices, and hospitality venues. Coasters come in disposable forms, such as paper or cardboard, and in reusable forms made from cork, wood, ceramic, stone, silicone, leather, or fabric. Many designs are decorative as well as functional, and some incorporate absorbent cores or non-slip bases to reduce sliding.

Sizes typically range around 3.5 to 4 inches (9 to 10 cm) in diameter for standard beverage glasses. Absorbent coasters, often made of paper or cork with a top decorative layer, draw moisture quickly; non-absorbent coasters use surfaces like ceramic or metal with a protective coating. Cleaning methods vary: dishwasher-safe ceramic or silicone can be washed, while cork or cork-backed may require wipe-clean care to preserve finish. Branding and artwork are common in commercial settings.

Roller coasters are amusement rides consisting of a track on which wheeled cars travel, typically with gravity-driven drops, turns, and sometimes inversions. They originated in the 19th century, with early wooden coasters and later steel designs enabling sharper drops and complex elements. Notable materials are wood, steel, and hybrids, with variations in track layout, train design, and capacity. Modern coasters emphasize rider safety, engineering reliability, and themes.

Across contexts, “coaster” refers to both the protective drink accessory and the thrill ride, reflecting the term’s broad sense of “one that coasts” or supports movement, whether of a beverage or a rider.