Confusion over the term pit bull/terrier

Question

I understand that in a lot of people's minds, including my own, there is confusion over the term "pit bull". I've read the Wikipedia article on "Pit bull" and it explains that it's not a a dog breed, but a generic name that encompasses a number of different breeds. Quoting the introductory paragraph:

Pit bull is the common name for a type of dog descended from bulldogs and terriers. The pit bull-type is particularly ambiguous, as it encompasses a range of pedigree breeds, informal types and appearances that cannot be reliably identified.

From this blog there are two photos of dogs that the blogger has labelled the "Pit Bull Dog", however after searching there is no officially recognized name of this type. In the blog it is mentioned that this "Pit Bull Dog" is also known as the American Pit Bull Terrier, which indeed is a recognized breed of dog.

I'm particularly confused because of the differences in appearance between the dogs in photos purportedly of American Pit Bull Terriers. On this blog site we have these two:

And in other places these are also American Pit Bull Terriers: From Wikipedia:

Top left: American Pit Bull Terrier
Top right: American Staffordshire Terrier
Bottom left: Staffordshire Bull Terrier
Bottom right: American Bulldog

From what I can see there is quite a large difference between the first two photos and the photo at the topleft of the last picture.

Similarly, the following photo is the main photo at the beginning of the American Pit Bull Terrier article on Wikipedia, and although in this case I see more of a resemblance to the first two photos I posted, to me it seems there are quite significant differences. The first two photos show dogs that are much more short-legged and stocky. Also the faces looks quite different to me. And how about the ears?

Assuming these are all photos of the American Pit Bull Terrier (for the montage image I'm referring to the topleft photo only), is it my imagination that there are massive differences between each individual of the American Pit Bull Terrier, even greater differences than one would see between individuals of most other breeds of dog?

And I also found these images in an image search. Essentially they distinguish an American Pit Bull Terrier and an "American Bully":

(APBT standing for American Pit Bull Terrier)

I don't know what the American Bully is, but they surely do look like the American Pit Bull Terrier from the first two photos. Can someone help clear up my confusion?

Answer 1

The final three images I posted in the question are spot-on when they say "Learn the difference" and "Stop the confusion." As mentioned in the Wikipedia article, the term "pit bull" is a common generic name used by many for a number of dog breeds. Wikipedia includes the following image to show some breeds that may be colloquially called "pit bulls". Here are some of them:

Top left: American Pit Bull Terrier
Top right: American Staffordshire Terrier
Bottom left: Staffordshire Bull Terrier
Bottom right: American Bulldog
(courtesy of Wikipedia)

I can understand people not being able to distinguish some of these dogs, but it's strange that the first two images shown in my question are named "Pit bull" dogs. Although I'm not good at identifying dog breeds, the first two images are most likely of the American Bully. I had never heard of this breed, and didn't know that a Wikipedia article for this dog breed existed (American Bully). So it seems that now many lump the American Bully - a dog with huge differences in appearance, and only a few decades old - into this imprecisely defined term "pit bull". That is, this guy or gal:

I think these dogs must work out, or something.

Some sources I've checked say that the creation of the American Bully from selective breeding began in the 90s, but the Wikipedia article says that it began between the 80s and 90s. The breeding apparently began initially by mixing the American Bull Pit Terrier and the American Staffordshire Terrier, and subsequently other dog breeds. It's generally agreed that the dog breeds included in this selective breeding included the Staffordshire Bull Terrier (the English one), and various bulldog breeds (The English and French bulldogs are probably where it gets it's flat face and short, stocky body).

It should be remembered that since the American Bully was bred partially from the American Pit Bull Terrier, and that the breeding in the United States was not a coordinated breeding program, there are significant variations in the American Bully, some of which resemble the American Pit Bull Terrier more than others.

It's interesting that while the American Bully looks more muscular, imposing, and (subjectively) scarier-looking, it's generally more gentle and calm than the American Pit Bull Terrier. This was an intention of the selective breeding for the American Bully, as the American Pit Bull Terrier's ancestors were bred as either hunting, baiting or fighting dogs in the 18th and 19th century in Britain. The American Pit Bull Terrier, due to either its temperament or perception thereof by certain authorities, is either banned or has strict prohibitions on it. Some American states and counties have banned owning one, alone with many other parts of the world such as in the UK, the Canadian province of Ontario, and other parts of the world.
American Pit Bull Terrier: Law

It seems that the plan of creating a more behaved, calmer and family-friendly dog in the American Bully has been largely successful, as most people will attest to this. That's not to say the American Pit Bull Terrier inherently is not well behaved or family-friendly however. I just say this generally speaking.

Also, the American Bully has limited recognition as an official breed of dog. It was only recognized by the United Kennel Club (American) in 2013, but is still not recognized by the American Kennel Club or the World Canine Organization, a federation of kennel clubs.