Do you have to use inc in a incorporated company?

Yes, when you incorporate your company you will have to choose some variation of Incorporation, Company or Corporation after your company name. You will need to choose either Incorporated, Inc,...

Run Joss Run lol

No, you cannot. The statutes of every U.S. State prohibit a non-incorporated business from using any of the four corporate name types: corporation, incorporated, inc. or corp. They also prohibit...

As Co is to Company

yes