During walks, there is only one option when it comes to getting all the clothes and stuff. Yes, two, if you have someone else carry it for you, but otherwise it’s probably backpack that apply.
Longer tours with much packing requires backpack with frame. The backpack gets more charter, and it is easier to fasten equipment while on the outside, such as tents and the like. The framework also means that better ventilation at the back. On the other hand, takes the backpack rather much space if you should stow it into, say, a car, and when climbing or very hilly terrain, the high center of gravity be a disadvantage.
Shorter tours when you only have with a thermos and a couple of extra socks are you able, of course, with a significantly smaller backpack on 20-30 litres. The hard part is to find an optimal size. If you choose a small backpack, you have to opt out of stuff you suddenly notice that you could have had. If you choose a large backpack, there is a danger that we are carrying unnecessary weight and tire themselves out unnecessarily. With good planning and experience will be a good bit of the way.
Longer tours with more packing requires backpack sizes of 60-120 litres. Make sure the rucksacks length fits your back, or that the length can be adjusted. Waist belt should be convenient and with chest straps and similar adjustments shall you be able to redistribute the weight without taking off your backpack.
Backpacks with pallet weighs a little bit but it is nice to be able to sit comfortably during hunting, for example, pass, fishing trip or day trip. As long as you wear it on your back gives it a certain degree of Charter for the gasket.
Most modern backpacks have room for a water bladder that makes it easy to quench your thirst without having to stop and look for the bottle, which is usually at the bottom.