Hitting the Hay

Hitting the hay is an expression for going to sleep. Even when a far greater percentage of English-speaking society lived on a farm, humans did not actually sleep on hay itself; hay is made of straw, and straw prickles. Many domesticated animals, however, can sleep on hay just fine. More importantly, hay stuffed in sacks was often used as mattresses in the United States at the start of the 20th century (circa 1900). Thus, hitting the hay became an idiom for laying down on one's bed and going to sleep. Ex.: "I'm going to hit the hay right after making this last blog post..." This means, I will go to sleep after making this last blog post.