Dogs have been selectively bred for thousands of years, sometimes by inbreeding dogs from the same ancestral lines, sometimes by mixing dogs from very different lines. The process continues today, resulting in a tremendous variety of dog breeds.
The following list uses a wide interpretation of "breed". Breeds listed here may be traditional breeds with long histories as registered breeds, rare breeds with their own registries, or new breeds that may still be under development. Please see individual articles for more information.
In a dog show, judges familiar with specific dog breeds evaluate individual dogs for how well they conform to published breed standards, hence the more accurate term is conformation show (or, sometimes, breed show).
"Dog show" is often used by the general public to refer to any event involving dogs, such as dog sports, but in the dog world it more specifically refers to conformation competitions.
Handlers set up their dogs for judging so that their stance is perfect when the judge views them.