What is the origin of the idiom "hit the sack" and when to use it?

The idiom "hit the sack" has its origin in the association of a "sack" with a bed or a sleeping place, dating back to the early 20th century. It refers to the action of going to bed or preparing to sleep, emphasizing the idea that one is physically hitting or getting into their bed or sleeping arrangement. The expression is now commonly used to indicate the act of going to sleep or getting some rest.