Snow crystals are single crystals of ice while a snowflake is one or more crystals stuck together. Water molecules create a hexagonal lattice that is formed when water vapor condenses directly into ice in clouds when the temperature is freezing or below. There are several factors that influence the shape of snowflakes: humidity, temperature, and air currents. Colder temperatures create more intricate shapes – sharper tips and more branching.
I find that a good snowstorm does wonders for my ability to write and read. Writer Nathaniel Hawthorne felt the same way. “Snowflakes” collected in Twice-Told Tales, 1837, is a wonderful read as the snowflakes come down. http://www.islandnet.com/~see/weather/arts/snowflakes.htm
Snowflake photographs used with permission of snowcrystals.com