Backpack (from the German Rucksack - shoulder bag) - a specialized bag for carrying equipment, food, personal belongings, etc. on the back. Supplied with two straps.
When carrying a backpack of small and medium volume, the load is placed on the shoulders and back, while the large backpacks are equipped with a special unloading belt that carries the main load on the stronger hips, so that the shoulder straps are mainly used to hold the backpack in an upright position. In both cases, the arms remain free. The backpack is suitable for carrying relatively large loads for a long time.
The predecessor of the backpack is the army backpack, which became widespread in the XVIII-XIX centuries. Nowadays you can still find school bags. In the post-war years, simple backpacks made of tarpaulins were widely used, often sewn in a handicraft way.
The main "users" of backpacks for a long time remained sportsmen - tourists and climbers. In particular, in the middle of the XX century the outstanding Soviet climber Vitaly Abalakov developed a backpack for sports hiking and climbing, called by his surname "abalakovskiy" or "abalak", which for a long time was a standard, and mostly the only available in the former Soviet Union, element of sports equipment.
All significant changes in the design of backpacks were invented and implemented, starting from the middle of the XX century, usually constructively supplemented by "abalak". From the middle of the '70s, the first completely home-made tourist and mountaineering backpacks appeared. Homemade handicrafts quickly became popular among tourists and mountaineers. It was on the home-made designs that belt belts appeared for the first time.
Not surprisingly, after the military convenience of the backpack was appreciated by athletes and tourists. The first one was that hands were always free, and the second one - it was much easier to carry a lot of weight on two shoulders than in one hand. And this even though in the post-war year's backpacks were made of heavy tarpaulins and weighed a lot by themselves.
However, times are changing, and so are materials. Therefore, when the general fashion for sports lifestyle, sportswear, and accessories began, backpacks became fashionable. And at the moment they occupy a huge place in the life of modern man.
Especially often on the streets, you can find backpacks of such companies as Adidas, Nike, Puma, Reebok, Dakine, Burton, Salewa, Tatonka, Deuter, made of light and durable fabric. Even laptop bags now replace special backpacks for carrying the computer behind your back.
Modern backpacks are made not only of different materials but also of different shapes. If you do not take into account children's and decorative backpacks, the rest are measured in liters. If all backpacks had the form of a parallelepiped, everything would be simple: multiply the height by length and width, and that's all.
But the shapes are different, so a liter glass of sand is used to measure - how many of these glasses will fit, and this is the volume of the backpack. However, the volume of the backpack with a volume of 40 liters varies from company to company. This depends on whether the volume is measured with or without pockets. However, backpacks of one company are measured only in one way.
In addition to the fact that backpacks may or may not have a "basement", they are divided into three main types. But first, the "basement" is a small compartment at the bottom of the backpack, which can be accessed with an additional zipper. Some people don't think it's very convenient, because the complexity of the system makes it harder to resist.
Others find it much more convenient to open the compartment from below than to dig into the depths of the entire backpack to get something from the bottom. Sometimes these "basements" (a tube of thinner fabric) are made at the top, which allows you to increase the volume of the backpack if necessary.
The three types of backpack include a "bun", an easel and a "pipe". "Kolobok is around shoulder bag with two straps. Relatively recently, such backpacks were called "death of a tourist" or "death of a pioneer" because of their uncomfortable distribution of the center of gravity - a person in such a backpack could easily lose their balance. Also, its great disadvantage can be called the inconvenience of a sock: if you put something hard in the "bun", it will rest on the back.
The backpack is equipped with an aluminum or titanium frame, which redistributes the load and gives the backpack a shape. The backpack is mounted on one side of the frame, and on the other side - shoulder and waist straps to redistribute the load. Such backpacks are bigger and more massive than "koloboks", but to carry something big and heavy in them is much more convenient and easier.
The majority of modern tourist backpacks have the form of a "pipe", a soft backrest made of breathable material, comfortable shoulder straps, a waist strap and if the backpack is designed for high weight, the chest strap that connects the front shoulder straps.
This system allows you to conveniently distribute the weight of the backpack throughout the body. The size of such a backpack can reach 130 liters (for comparison: machine tools of more than 100 liters are practically not found). But, thanks to the lightweight fabrics, its weight is not very high.
Separately there are various sports backpacks, which are selected for a particular sport. These can be a backpack with a ski mount, a lightweight mesh backpack, a backpack with a ventilated backrest, or a backpack with an extra head strap, which allows you to better feel the balance while going downhill on skis.