Backpacks are a wonderful invention. They allow people to carry things yet have their hands free. Whether you are using your backpack as luggage for a long air flight or to hike down one of the many famous hiking trails, it needs to conform to your size and your ability to carry weight. A framed backpack should settle the weight on your hips as much as on your shoulders and back. This relieves stress on your spine, but means making sure your backpack fits you. While they can be adjusted, one size does not fit all.