A screw top is a type of closure commonly used for bottles and jars. It consists of a threaded cap that twists onto a matching threaded neck, providing a secure seal. This design is popular for packaging beverages, sauces, and other liquids, as it is easy to open and reseal. Screw tops are often made from materials like plastic or metal, and they can be found on products ranging from wine to soda. They offer convenience and help preserve freshness by preventing air from entering the container, making them a practical choice for both manufacturers and consumers.