A backpack (also called rucksack, knapsack, packsack, pack) is, in its simplest form, a cloth sack carried on one’s back and secured with two straps that go over the shoulders, but there can be exceptions. Lightweight types of backpacks are sometimes worn on only one shoulder strap. Backpacks are often preferred to handbags for carrying heavy loads or carrying any sort of equipment, because of the limited capacity to carry heavy weights for long periods of time in the hands.
