What breed of dog is this?

That is a black Chow Chow. I know there is one breed that the Chinese breed a lot of black chows. In the US ppl usually want the orange color. Unless you live someplace cold year round I would not recommended this dog as it as a thick coat. They also are not very human/other dog friendly. They are almost always NOT children friendly. Of course there are those occasional awesome ones that are.. If you have kids under the age of 13 in your home I would not get this.