How to use Mrs., Ms. and Miss for names?
"Mrs" means the woman is (or has been) married; "Miss" means she has never been married but is not used that much any more excepting when addressing young girls. "Ms" means either of the above but the woman prefers not to reveal which. You can also use "Ms" if you don't know if the woman is married, unmarried or widowed. If writing someone that you are unsure of, you can just use a capital "M." because some married or widowed may not like to be address as "Ms."