Black is the "default" eumelanin color for dogs. A dog that isn't homozygous for chocolate or liver in other breeds (brown) (bb) or for dilution (dd) will have black eumelanin. This means that it will have a black nose and, most of the time has brown eyes, and any eumelanin in its coat will be black.
Dominant Black Examples
All of these dogs are Kk or KK on the K locus, making them genetically dominant black. Notice the lack of red anywhere in the coat of any of the black dogs
Black with White
There are variation with the color black
Black Spotted on White
Black with Tan Points and White Markings
Black with Tan Points Spotted on White (this is also called Piebald in some breeds)
Black with Tan Points Spotted on White also but much more white than the above dog.
Black With Fawn Points with white markings and Black Brindling