Storm windows are additional windows installed on the exterior or interior of existing windows to provide extra protection against severe weather. They help reduce air leaks, improve insulation, and can prevent damage from high winds, rain, and flying debris during storms. These windows can be made of various materials, including glass and acrylic, and are often designed to be removable. Installing storm windows can enhance the energy efficiency of a home, reducing heating and cooling costs while also increasing comfort during extreme weather conditions.