A hybrid dog breed (also called designer or mixed breeds) is the result of crossbreeding two or more different purebred dog breeds. Generally this is done to produce offspring which inherit the desirable traits from each purebred breed. For example, crossing a golden retriever with a standard poodle (called a golden doodle) can produce offspring with golden retriever traits and the hypoallergenic coat of a poodle.
Ideally a hybrid dog will only contain the best traits of both the purebred breeds. However, this is not always the case as hybrid dogs will not inherit the same traits from their parents so it is possible for some hybrids to inherit undesirable traits from their parent breeds.