Rain and Snow are forms of precipitation or in other words, water that drops from the sky as a result of condensation. Water usually evaporates and goes up and when it cools it condenses and it falls as rain or snow, or just moisture. In case you are asking, no I don't plan on becoming a meteorologist anytime soon.
Rain and Snow are good and make nature look great.
By the way, these images are in public domain, I do give credit to the original photographer.
They promote plant life (rain only, not snow) They provide nutrients for the crops to grow. The precipitation is needed to ensure that no part of the land goes dry, or otherwise be stuck in arid conditions, like this:
Now there are some major drawbacks!
Commuting is hard with this weather. Operating a car and navigating is much harder. Tires may not work properly, especially with loads of snow. Too much rain can mean flooding. We don't need too much water, we just need the right amount to grow our plants and our crops. I don't know the real benefits of having snow other than the fact we can play with it.
I say this now because we are expecting a major snowstorm to hit New York City today.