In addition to their use in outdoors pursuits, backpacks are sometimes used in other sports as well. Hydration packs, sometimes used by athletes and military personnel, carry water (in either a bladder or a rigid bottle) and have a tube connected to them from which the wearer can drink without removing the pack; this feature is also included in some more general-purpose hiking backpacks. Backpacks that carry skateboards have also become more popular in the youth culture.
Backpacks are a standard part of the load-bearing equipment of soldiers, especially infantry, in most countries, and military-style packs are regularly available to civilians in military surplus stores. Well-known examples include the United States ALICE field pack and the British Army PLCE rucksack attachment, both of which are widely available to civilian markets both as actual military surplus (new or used) and as replicas. Such packs are often, though not always (e.g. the USMC's ILBE pack), external-frame packs, with the pack itself lashed or pinned to a metal or plastic carrying frame. For units that are entering combat situations, packs may be loaded heavily and can weigh in excess of 100 lbs. Each soldier may carry extra weapons, ammunition, rations, medical supplies, tents or other shelter material, and extra clothing.
The simplest backpack design is a bag attached to a set of shoulder straps. Such packs are used for general transportation of goods, and have variable capacity. The simplest designs consist of one main pocket. This may be combined with webbing or cordage straps, while more sophisticated models add extra pockets, waist straps, chest straps, padded shoulder straps, padded backs, and sometimes reflective materials for added safety at night. These packs are generally produced inexpensively.
I actually use this tote as a diaper bag, I have two children in diapers and it really works great for that. Aside from the way I use it, I think it's an over all great bag. A few issues: the elastic pockets on the sides seem to have lost their tension already, I don't put anything large or heavy in them to cause this, also the pocket in the back.. Wish it was larger, I don't really see the point of the zipper in the bottom of the pocket. The only other issue I have is the straps, wish they had some sort of padding on them, they tend to be a little hard on your hands if you're carrying anything heavy.