terminology!
The word backpack was coined in the United States in the 1910s. Knapsack and packsack were used before; they now occur mainly as regionalisms in North America. The word rucksack is a German loanword mainly used in the UK and in the US Army: der Rücken means the back (the part of the body) in German, Sack stand for bag. The name Rucksack is cognate with Danish Rygsæk, Norwegian Ryggsekk, Dutch Rugzak, Afrikaans Rugsak and Swedish Ryggsäck. Alternative names include Haversack, and Bergen in German language called Kraxe.
The word knapsack originated in Britain in the 1930s as a term for the bag worn by young school children to carry afternoon knap supplies, such as a pillow and blanket. These wearable bags were also used to carry lunches to school, but the name bangersandmashsack did not meet with the same popularity as knapsack.
Backpacks can often simply be referred to as packs, especially in outdoors contexts; though sometimes ambiguous compared to other bags such as saddlebags and duffel bags, context is generally sufficient for identification.
A backpack fitted with pocket(s) that are suspended on the wearer's front side (chest) and loaded in such a way that the load in the front and the load in the back are about equal is called a bodypack. The majority of the load on a bodypack is carried by the hips.
The ideal load carrying system should not disturb the natural posture, balance and movement of the body. The load must be dispersed onto the skeletal structure in a balanced way. The load should not produce forces on the body in the direction fore, aft, right, or left. This body-centered load carrying system is a bodypack.
Invention of the Backpack
Kelty was an avid hiker. He used to hike the countryside of the Sierras. Of course, it was difficult for him to carry his hiking gear with the old ways or carrying weight and so he wanted to develop something that’s more efficient and capable. So, he started experimenting. Back in those days people used to rely on military surplus stores. The problem was that the gear found at military surplus stores was generally pretty heavy and quite coarsely designed.
In 1951, while hiking, Dick Kelty along with his pal Clay Sherman decided to put the load of the equipment from their shoulders to their hips. In order to do this, they had to skid the ends of their pack boards into the rear pockets of their jeans. This was when both of them realized that this is a much easier and comfortable way of carrying load. Kelty was impressed with this idea and he kept working on it to make things better.
Kelty then came up with the idea of adding a hip belt to the standard wooden frame and worked on it further. This was when Kelty thought of changing the wooden pack design to a more lightweight design by using lighter materials such as aluminum and by changing the rucksacks to nylon. Kelty’s wife came into the game and sewed the rucksacks to fit the frames. This was the start of a revolutionary home based business of backpacks. By 1952, Kelty was able to sell 29 backpacks for $24. But, this wasn’t where Kelty stopped. He kept on amending the design. Later on he added shoulder straps, padded waist and exterior zipper pockets to his packs.
During the 70's, outdoor activities such as hiking became quite popular and more and more people were going for it. This was when Kelty’s backpacks became famous since most hikers of the area and the nearby areas started purchasing them. With time, the backpacks became so popular that others started making them too. Hence, things improved with time and wooden packs were transformed into backpacks as we know them today.