Crawling, in humans, is a type of movement that engages all four limbs. It is one of the earliest forms of movement learned by human babies, as it precedes one’s ability to walk on two legs. Aside from being a preliminary form of movement in children, one might crawl because of an inability to walk on two legs, perhaps due to a disability, drunkenness, or injury. One also might crawl when in a confined space with a low ceiling, such as a cave or beneath a table, when searching for something on the ground, when trying to avoid detection, and so on.
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