Some people think that explaining how something occurs "ruins" it, but I think that's wrong. I have some knowledge of how ice crystals form in damp air, and because of that I look at these pictures and marvel more.
"Blueprint", about halfway down on the right side, is my favorite. It's largely a hexagonal plate, but inside it there is another, smaller hexagonal plate, off center, that stuck to the first snowflake while it was forming.
"Capped column" is also amazing.
Snowflakes are ice crystals, and like any other crystals their shape is dependent on the shape of the molecules that form them. In the case of water, there is a 120° angle between the two hydrogen atoms as they cling to the oxygen atom. Why is that? Why isn't it a 180° angle, or 90°, or something else? Well, because the entire point of atoms forming a compound is to share electrons, and this way the oxygen atom and the hydrogen atoms all have full electron shells at the lowest possible energy. The result is that 120° bend; and that 120° bend means that crystals will tend to be hexagonal, or equilateral triangles.
Snow happens all over the world, all the time, snowflakes forming in infinite variety and beauty, and nearly all of them go entirely unnoticed.