Dragons

Smaug is a red dragon in the Hobbit...but I don't know if the film will show him that color.

At the same time, the favorite hobbit tavern is the "green dragon".

What's the difference?

Dranconika discusses it here:

Red dragons are greedy and covetous, and obsessed with increasing their treasure hoards. They live in warm habitats, such as volcanoes or tropical islands. The red dragon's domain is is the mountain and the island....
The green dragon is a belligerent creature and master of intrigue, politics, and backbiting. He is cruel. He prefers forests—the older and bigger the trees, the better. Instead of being overtly aggressive, he prefers to concoct elaborat schemes to gain power or wealth with as little effort as possible ...

in contrast, the Chinese dragon is more worm like, lives in rivers/the ocean, and helps protect people.