What do Americans call backpacks?

What do Americans call backpacks? In the United States, I’m not sure most people would even know what a “rucksack” is. The most common word here is “backpack,” but there is also “bookbag” or “knapsack,” though knapsack is becoming rather outdated.

In the United States, I’m not sure most people would even know what a “rucksack” is. The most common word here is “backpack,” but there is also “bookbag” or “knapsack,” though knapsack is becoming rather outdated.