An ancestral file number is like a special code that helps you find out information about your family history. Imagine that your family is like a big puzzle, and each person in your family is a piece of that puzzle. An ancestral file number is like a number that identifies each piece of the puzzle. When you have the number, you can use it to search for more information about that person in records like birth certificates or census records. The number makes it easier to connect all the pieces of your family puzzle together and learn more about your ancestors.