A flask is a small container, often made of glass or metal, used to hold liquids. They are commonly used in laboratories for mixing and heating substances. Flasks come in various shapes and sizes, with the most popular being the Erlenmeyer flask, which has a wide base and a narrow neck. This design helps prevent spills and allows for easy swirling of liquids. In everyday life, flasks are also used for carrying beverages, like coffee or alcohol. A thermos flask is designed to keep drinks hot or cold for extended periods. These flasks are handy for picnics, camping, or simply enjoying a warm drink on the go.