The world is crazy over backpacks. You see them everywhere. Kids, students, professionals and adventurers all use them. It's no wonder. Backpacks are useful, practical and are more stylish than ever.

There's just something about a backpack that we love. Maybe it's the sense of independence that we feel when carrying stuff on our back with hands free. Maybe it's the security of having all that we need right with us. Whatever the reason, few realize that the backpack revolution is relatively young and that the modern backpack is less than 100 years old.

So, let's take a quick look at the intriguing history of the modern backpack.

It's likely that backpacks have been around since man began to roam the earth. The earliest backpacks were made of various materials including animal skins. Most early packs were small compared to those we have today. The weight of the leather and a lack of support were likely influencing factors in the small size of ancient packs.

Later, external wooden frames were added to increase the stability and support of early backpacks.

Some people groups also wove large basket-like packs. They secured them to their waist, shoulders and even their head for stability. These can still be seen in various Asian and South American cultures.

In the American Civil War, it was necessary for troops to carry their basic belongings for extended periods of time. Even so, the packs used at this time were generally small in size and had little, if any, frame to distribute the load. A change of clothes and a bedroll, were just about all a man could fit in his pack.

It was not until the 1920s, that an American named Lloyd Nelson, improved upon a native American design that used seal skin and willow branches to form a sizable backpack. Nelson came up with a much improved pack and soon mass-produced it. The modern frame backpack was born. He called his invention the Trapper Nelson.

Popularity of the Trapper Nelson grew quickly due to many factors. America was becoming more mobile. Roads were being built, while State and National Parks were being opened. America was discovering its vast natural resources and wanted to get off the path and explore. The modern frame backpack made it possible for Boy Scouts, hunters and campers to comfortably travel long distances on foot to secluded wilderness areas.

Innovations in backpacks continued, as strong, lightweight, synthetic materials came on the scene in the 1960s and 1970s. With more people wanting to "get back to nature" manufacturers responded with new, super-lightweight, internal-frame packs.

In the 1980s, backpacks got another boost in popularity. Students needed to carry larger textbooks and other gear back and forth to school. The result was an explosion in new backpack designs.

In the 1990s, many other bags were no longer suitable to comfortably carry and keep laptop computers and other electronic devices safe in transport, so pack designs evolved to incorporate pouches for computers and other personal electronics devices.

Today, backpacks continue to rise in popularity with 50% of Americans owning at least one. Students of the 1980s and 1990s are now professionals. With "casual" being the trend, many white-collar workers are tossing their briefcases and reacquainting themselves with a dear childhood friend... the backpack.