A backpack (also called rucksack, knapsack, packsack, pack, Haversack, or Bergen) is a bag put on somebody's back. It usually has two straps that go over the shoulders. It is used to carry things in it, and it often has many pockets or compartments to carry things.
Safety- a backpack enables you to carry your belongings safely. Most backpacks are waterproof, lightweight and flexible, and they provide maximum protection for the products inside them. Using a backpack also means that your belongings are kept closer to your body, making it difficult for thieves to steal.