Snowflakes provide us with a great example to illustrate how organized structures can be created out from randomness. The creation of snowflakes is actually very complex, and the exact mechanisms that give rise to them, and their particular symmetrical shape, are still under debate. However, we can think in a simple model, which is the basis to construct the below GIF: imagine a frosted surface (in this gif at top and bottom), and water molecules wandering in the air. When these molecules hit the frosted surface they aggregate and thus the snowy surface begins to grow. As this surface grows, some places of this aggregation are more likely to be hit, and as a result, we end up with a shape that, however random, exhibits some self-simmilarity properties (like fractals).
