Ranging from the smug to the foolish and the all-out Cheshire cat smiles, these adorable cats will certainly improve your day, no matter how awesome or tough it's been.

We also all know cats are mysterious, so where do these adorable animal smiles come from? Strangely enough, the ones on their faces aren't true smiles, as their facial muscles are not the same as humans. So, technically, smiling animals aren't really smiling. More often than not, your cute cat will express happiness via the obvious purring, closing their eyes, and relaxing their head backward.

Anyway, we'd love to hear which of our happy animals are your favorites, and as always, feel free to submit your own examples of smiling cats and happiness!