Here's Tard with her brother Pokey:

They are Snowshoe Siamese; see the Snowshoe Wikipedia page for more.

Inquisitr adds:

Tardar Sauce, or “Tard” for short, isn’t angry at the world. According to News.com.au, this seemingly grumpy cat is actually a very happy and loving kitten. “Tardar has what looks kind of like an under bite. She looked unique, as did her brother, at birth, with a flat face, bubble eyes, and a short tail,” owner Tabatha Bundesen explained.

However, the grumpy cat’s owner did admit there might be other reasons the feline is a little testy. “Tardar is not as coordinated as a normal cat, so she is likely a little angry about that. I think she likes to be held and petted some times, but being the pet of a 10 year old could make anyone grumpy,” Bundesen admitted.

What kind of cat is Tardar Sauce, you ask? According to a helpful reader at Paw Nation, the grumpy cat is a Snowshoe Siamese. “Unfortunately, this one has some very bad genetic defects,” the visitor wrote. “The likely cause is inbreeding due to the small gene pool available for breeders. Do a Google search for this breed to see what they are supposed to look like. They are actually a stunningly beautiful cat. This one, of course, has his own kind of beauty!”

So there you have it. Now, enjoy this Tard the Grumpy Cat video:

Grumpy cat is clearly defective! This is what it's supposed to look like:

http://upload.wikimedia.org/wikipedia/commons/4/4b/Snowshoe_%28cat%29.JPG

Grumpy Cat Stash: http://pandawhale.com/ifindkarma/grumpy

Grumpy Cat Tumblr: http://tardthegrumpycat.tumblr.com/

Grumpy Cat Tumblr Tag: http://tumblr.com/tagged/tardar

Grumpy Cat Reddit: http://reddit.com/r/tardcat

And you can find the very best Grumpy Cat gifs here.