Backpacks are bags that possess two shoulder straps which allow the wearer to carry the bag on their back. Backpacks are often associated as a student's must have school accessory for carrying books, etc from class to class.
About Bags:
Bags are sections of material or fabrics that are utilized to carry objects. Bags can be any variety of sizes, colors and shapes.
About Metallic:
Metallic refers to a material that represents or resembles metals such as gold, silver, or pewter. Metallic articles are very shiny, and often embellished by metal materials.
