The process when snowflake crystals form is called "crystallization." This occurs when water vapor in the atmosphere freezes into ice crystals. As water vapor cools and condenses, it begins to bond together into a hexagonal lattice structure, which is characteristic of snowflakes. The specific shape of a snowflake is influenced by temperature and humidity conditions during its formation, leading to the famous saying that no two snowflakes are exactly alike. This fascinating process not only creates beautiful natural phenomena but also plays a significant role in Earth's climate and water cycle.