A home rule municipality in Pennsylvania is one incorporated under its own unique charter, created pursuant to the state's Home Rule and Optional Plans Law and approved by referendum. "Local governments without home rule can only act where specifically authorized by state law; home rule municipalities can act anywhere except where they are specifically limited by state law". Although many such municipalities have retained the word "Township" or "Borough" in their official names, the Pennsylvania Township and Borough Codes no longer apply to them. All three types of municipalities (cities, boroughs, and townships) may become a Home rule municipality.