Bottle stoppers are a type of closure used to seal bottles and jars. They come in a variety of shapes and sizes, and can be made from different materials. The most common types of bottle stoppers are plugs, CORKS, and caps. Plugs are typically made from rubber or plastic and fit into the neck of the bottle, while CORKS are made from cork and fit into the neck of the bottle. Caps are usually made from metal or plastic and fit over the top of the bottle. All three types of bottle stoppers are used to keep air and contaminants out of the bottle, and to keep the contents inside fresh.