Snow is a form of precipitation in which the falling water starts as miniature ice crystals.
What it is
Tiny ice crystals formed in clouds whose shape varies based on temperature and humidity. Shapes range from the famous six-fold radial symmetry to simple needles and columns. Thus, the claim "every snowflake is unique" and the nauseating phrase "special snowflake" is somewhat misleading. While not every six-sided variant of snowflake is unique in terms of shape, two are rarely alike.
What it's not
Crazy nanomachines from the government, somehow related to chemtrails. When a chunk of snow is burned at any temperature with a butane lighter, the snow does not seem to liquefy but rather turns black and shrinks. In actuality, the melted snow in liquid form is absorbed back into the snowball and the blackness is from the carbon in butane (C4H10) attaching itself to the snowball.
Snow also doesn't disprove the existence of climate change. In the real world, climate change can cause more wild storms to occur as more water is vaporized into clouds with wind being stronger in these instances.