Grin

The Grin is one of the basic smilies, consisting of a yellow face with black eyes and a white grin. It also has slight rosy cheeks.

Usage
The Grin is used to show a player's happiness for something, and is usually 'happier' than the Smiley. It is usually only used by guests or player's who have no other smileys.

Origin
The Grin comes from the ':D' emoticon.