A metal door is a type of door made primarily from metal materials, such as steel or aluminum. These doors are known for their durability and strength, making them a popular choice for both residential and commercial buildings. They provide enhanced security compared to wooden doors and are often used in areas that require additional protection, such as warehouses or bank vaults. Metal doors can come in various styles and finishes, allowing them to fit different architectural designs. They are also resistant to weather elements, which makes them suitable for exterior use. Many metal doors are designed to be energy-efficient, often featuring insulation to help maintain indoor temperatures.