A vacuum bag is a type of bag that is used to seal and remove the air from a space in order to create a vacuum. This can be done for a variety of purposes, such as storing items, preserving food, or packing fragile items for shipping. Vacuum bags are typically made of a plastic material that is capable of withstanding the pressure created by the vacuum and can be sealed using a vacuum sealer, a device that removes the air from the bag and seals it shut. Some vacuum bags are also equipped with a one-way valve, which allws the air to be removed from the bag but not to re-enter it, further enhancing the vacuum effect.