Let me start out by saying that it's an urban legend that Eskimos have over 100 words for "snow". See this post from Oxford University Press to find out more. Nevertheless, there ARE multiple words for the white stuff! Here are ten:
1. Corn Snow - Large, grained, rounded, coarse, granular wet snow formed by cycles of melting and refreezing. A crust may form on top of the snow (even holding the weight of a person), but will turn to slush later in the day. It's usually formed in the spring, during sunny days and and clear, freezing nights.
2. Firn - Granular, round, well-bonded snow--especially on the upper part of a glacier--where it has not yet been compressed into ice (an intermediate stage between snow and glacial ice).
3. Hoarfrost - Tiny, spiky, dendritic, delicate ice crystals formed by the same process as dew, but results when the temperature of the surface is below freezing point, usually attaching to grass, leaves and branches. (To know what "hoary" means, click here.)
4. Sleet - Rain mixed with snow. (I stand corrected by my 9th grade science teacher, Mr. "Pye" Plasko!) → Rain drops that freeze on the way down. TV weather casters often call this a "wintry mix". Sleet can contain ice pellets, but they're much smaller than those found in hail (and are technically called "graupel").
5. Rime - Crunchy, rough snow that often looks like styrofoam. Super-cold droplets from fog instantly freeze on solid surfaces, forming a think coat. Rime, too, can look spiky--but they're larger spikes that face towards the wind. Unlike hoarfrost, rime is solid white. Sometimes, rime can result in "snow ghosts" (aka frozen fog). Click here to read a travel story about tourists hunting frozen fog in China.
6. Slush - Partly melted snow on the ground. If it were coming down from the sky, it would be sleet. (I stand corrected once again!)
7. Polycrystals - Large snowflakes formed many individual ice crystals.
8. Powder - New, dry snow composed of loose, pristine ice crystals.
9. Névé - Also related to glacier formation, Névé is granular snow that has been partially melted, refrozen and compacted. If it survives a full melt season, it becomes Firn.
10. Sastrugi - Imagine ripples among sand dunes--but as snow, instead. Formed by wind erosion, these irregular grooves and ridges can span centimeters or several feet.