"Snow White" is a fairy tale widely circulated across Europe. The most famous version is from Germany's Grimms' Fairy Tales in 1812; the character of Snow White might have been inspired by a noblewoman from western Germany in the early 18th century.
The "Snow Queen," on the other hand, is a fairy tale created by Hans Christian Andersen.
The story of "Snow White" is roughly as follows: Snow White, hated and hunted by her jealous stepmother, flees into the forest. There, she receives help from seven dwarfs but is later tricked into eating a poisoned apple, causing her to fall into a deep sleep. She is eventually awakened by a prince's kiss, and they marry happily.