A split pin is a special kind of pin that has two legs that are separate at one end and joined at the other. It looks like a tiny metal sword with two points. To use a split pin, you first make a hole in something you want to hold together, like a piece of paper or a toy. Then you put the legs of the split pin through the hole and separate them so that they stick out on the other side. Finally, you bend the ends of the legs down so they don't come out of the hole. This helps hold things together so they don't fall apart. Split pins are often used for things like holding car parts together or keeping important documents organized.