The "oh ya know, I'm just a lovable, silly, perfect pup... for now" smile.
The "way to cool to show my teeth" smile.
The "hey Ma, of course I'll look perfect for a pic to win points" smile.
The "I was taught to smile like this, so this is how I shall do it" smile.
My parents just got a dog, and I am now determined to get it to smile. Amazing.