Its Master's degree. anywhere you look it will come up Master's even if you type in Master. Also my aunt is a lawyer and I asked her, I even looked it up in the new Collage Webster Dictionary so it...
Really depends on the Major, and the Region, but there is generally a difference at the begining where a master's degree might expect to make more initially.
Salary and earning potential are strictly dependent on the type of field you are in, your position within that field, the institution you work for, experience, expertise, personal abilities, critical...