The pretzel is one of the world's oldest snacks, with origins tied to the Christian church. Legend has it that an Italian monk in AD 610 created the 'pretiola' (little reward) for children who learned their prayers. The unique twisted shape was designed to look like arms crossed over the chest in prayer. The three holes in the pretzel were said to represent the Holy Trinity. Pretzels became popular in Germany as a symbol of good luck and prosperity. In the 17th century, the 'nuptial knot' was used in weddings—where the couple would pull on a pretzel like a wishbone. The characteristic dark, shiny crust of a pretzel is achieved by dipping the dough in a lye solution (sodium hydroxide) before baking.