The form of precipitation composed of ice crystals is called snow. Snow forms when water vapor in the atmosphere freezes into ice crystals, which can accumulate on the ground. Each snowflake has a uniquely intricate structure, depending on temperature and humidity conditions during formation. Snow plays a critical role in Earth's climate system and water cycle, providing insulation for soil and reducing erosion. It also creates habitats for various species and enables winter sports, contributing to recreation and tourism in snowy regions.