Aluminum is a lightweight, silvery-white metal found in the Earth's crust. It is a pure element with the symbol Al and atomic number 13. Aluminum alloys, on the other hand, are mixtures of aluminum with other elements such as copper, magnesium, manganese, and silicon. These alloys are created to enhance certain properties like strength, durability, and resistance to corrosion. While pure aluminum is soft and malleable, its alloys are stronger and more versatile, making them suitable for a wide range of applications from aerospace to construction.