1. An ax is one of humanity's oldest tools. Early humans made axes out of stone and flint over 1.5 million years ago, long before metal was discovered! These stone age tools didn't even have handles—people held the sharp stone directly in their hands.

2. It works using a simple machine called a wedge. An ax head is a double inclined plane (two ramps placed back-to-back). When the sharp edge strikes wood, the wedge shape pushes the wood fibers outward in two opposite directions, splitting the log apart.

3. Firefighters carry specialized axes with picks on the back. Known as a pick-head ax, this essential rescue tool has a traditional cutting blade on one side and a pointed pick on the other, allowing firefighters to chop through wooden doors or pry open heavy debris.

4. The hole where the handle attaches is called the eye. To keep the heavy metal head from flying off during a swing, craftspeople hammer a small wooden or metal wedge into the top of the handle inside the eye to expand the wood and lock it tight.

5. Astronauts had a special survival ax on early space missions. During the Soviet Union's space program, cosmonauts carried a multi-purpose tool called the TP-82 in their spacecraft. It had a detachable ax handle that could double as a shovel if they landed far off course in the remote wilderness.

6. A small one-handed ax is called a hatchet. While full-sized axes require two hands and a wide swing to split heavy firewood, hatchets are small enough to hold with one hand for light camp tasks like trimming branches or making kindling.

7. Paul Bunyan's giant ax is a famous American tall tale. According to folklore, the giant lumberjack Paul Bunyan dragged his massive ax behind him as he walked across North America, carving out the Grand Canyon!