An ampoule is a small, sealed glass or plastic container used for storing and preserving liquid or powdered substances. It is commonly used in the pharmaceutical, medical, and cosmetic industries to package medications, vaccines, serums, and other sensitive substances. Ampoules are designed to maintain the integrity and sterility of the contents until they are ready to be used. They are typically single-use and require breaking or snapping the neck of the ampoule to access the contents.