Popular Mechanics:

The story of the Slinky begins with a mechanical engineer, a shipbuilding factory, and a mishap.

Mechanical engineer Richard James was trying to develop a new tension spring that could keep a ship’s equipment secure while the vessel rocked at sea. One day he accidentally knocked a spring off his worktable. The spring tumbled to the floor, landing on one of its ends, but instead of jumping back up, the spring flopped end over end, walking across the floor.

The experience gave James an idea: Something as simple as a spring could be a toy. He told his wife, Betty, about the experience, and she decided to come up with a name for the new walking spring. In 1944, when leafing through the dictionary in search of an appropriate term, Betty found a word meaning sinuous and graceful—just the way the spring moved and sounded as it flopped along. The word was “slinky.”

I love stories of the history of the Slinky. I’ve only ever had one and it was wrecked by a little brother very quickly but I’ve always thought the little spring was cool. But not the plastic ones. Those are awful.