I try to look objectively at the ubiquitous rucksack (also known as a backpack) but can only come up with one conclusion: I hate them. Rucksacks are ugly, impractical and uncomfortable. Someone wearing one knocks it into me at least once a day on the tube, not seemingly factoring in that they are twice the size whilst carrying one. And looking like a hunchback. The few times I have donned one, my shoulders ache, my back sweats and I'm always paranoid someone's going through the pockets. And I have to take it off to get something from it. Really can't believe they're so popular.
Rucksack is a German word mean back and pack; the term backpack comes from the States.