Pennsylvania is one of four states that differentiate themselves from their 46 American brethren by use of a different word. Like Kentucky, Massachusetts and Virginia, it officially goes by the lofty sounding name of “commonwealth.”

In practical use, there is no difference. It is the difference between pancakes and flapjacks — purely up to individual preference. According to the Merriam-Webster Dictionary, it was simply a term that some writers in the Revolutionary period liked to use, the way today some conservatives might favor the label of “libertarian” (with a small L) or a liberal might prefer the term “progressive.”