Seeds are the codes you put in when creating your world... which direct you to a certain biomes. All words do direct you to a biome but certain ones direct you to a very cool biome. This page is your 1-800 directory of seeds, and the best part is you won't find these seeds anywhere else because im the one that discovered them!
Here is how i write them and remember capitalization does matter.
Example: seed - date found - description - version
ENJOY!
Sasha - 04/6/12 - large mountain - Pocket Version
Kawarthas_luv_simon - 04/10/12 - Beautiful winter/jungle biome with lots of wolves and caves! - 1.2.5
I hate multiplayer - 04/9/12 - Basic forest, great for begginers! - 1.2.5