mass. is Massachusetts and md. is Maryland.
MA
Massachusetts
Max Aarons
PA and MA
Mikel Arteta
Maine
The initials for Arizona are AZ. All the states in the US have initials which are used as the abbreviation for a particular state.
In terms of educational degrees, it stands for masters of science (M.A.)
Maine --------------ME Maryland ----------MD Massachusetts ---MA Michigan -----------MI Minnesota ---------MN Mississippi ---------MS Missouri ------------MO Montana -----------MT
Richard Millhouse Nixon
To make it easier to identify states.
USA - United States of America For short US - United States