Are Pit Bulls a pure breed?

Patch O’ Pits writes:
The correct name of the breed is American Pit Bull Terrier and owners always have fondly referred to them also in short as pit bulls.
However now a days the term Pit Bull unfortunately has also become slang for any number of pure bred dogs and mixes that even somewhat resemble the APBT such as American Staffordshire Terriers, Staffordshire Bull terriers, America Bull dogs, Bull Terriers, many many different Mastiff breeds, Curs, Bandogs, and any other mix of those to name a few thus many classified by AC and the general public as Pit Bulls are in fact not even close to the breed American Pit Bull Terrier.

I wanted to add that lumping all these breeds together and referring to them as pit bulls or pit bull type dogs has tarnished the image of the breed by inaccurately inflating bite incident reports and creating undo public fear of the breed in general. It has also fueled some of the ridiculous myths surrounding this great breed