Visit Insider's homepage for more stories. Sometimes puzzles are so obvious that they're nearly impossible to solve.

Riddles push us to think in totally new ways that we don't normally use. Even riddles that seem silly and simple at first can keep our brains flexible and ready to see things in innovative ways we ...

Brainteasers have enjoyed a recent surge in popularity. These mental challenges are prized by people because of how fun they are, whether an individual partakes in them alone or in a group setting.