(11/1) condensation - the water droplets you see collecting on windows this time of year

It can also be seen on the outside of a glass of ice water in summer, or on the bathroom mirror after a shower.

I was asked this morning why the windows looked like they had a blanket on them.  This led to a nice discussion of the water cycle including the steam we see when we boil water to cook noodles, the formation of clouds, and the precipitation of rain and snow.