Archaeology explains the use of a "tally stick."
Imagine going to the local store in Wittenberg, Germany, in the midsixteenth century and not having enough cash to pay for the pig you wanted to roast for dinner. You might have to borrow some money and, in order to record your debt, the person making the loan would use a tally stick like this one. The stick was notched in the presence of both the lender and the borrower and then split in two, so that each person retained half. According to Andreas Hille, the state archaeologist responsible for Wittenberg, the contours of the stick and the distinct split guaranteed that only these two particular halves could be fit back together—insurance against anyone trying to cheat by adding more notches. When the borrower was ready to repay his debt, the two halves were put back together. The stick was then thrown away or destroyed.