A storm door is an additional door installed in front of an exterior door, designed to protect against harsh weather conditions. It typically features a durable frame and glass panels, which can be either fixed or removable. Storm doors help insulate homes, keeping cold air out in winter and reducing energy costs. These doors also provide an extra layer of security and can enhance the appearance of a home. Many storm doors come with screens that allow for ventilation while keeping insects out. Overall, they are a practical addition for homeowners looking to improve energy efficiency and protect their main entry doors.