The PhD usually involves three years of classes — with the extra classes often devoted to theory. In addition to the extra classes, most schools have a two day written preliminary exam at the end of the second year and an oral exam done near the end of the third year. After the oral exam, the student writes a dissertation — which must embody original and important research. This takes anywhere from one to five years to write. I did mine in about two years.

Most schools then have a dissertation defense. After that — you have a PhD.

Most of the top schools do not accept terminal masters students — except for special programs or professional programs (e.g., MBA or master’s in education). The academic programs at the best schools tend to accept PhD students. They will give out an MA or MS for students who pass the written PhD exam but fail to finish the PhD (or choose not to finish).

Lower ranked universities often offer an MS or MA in these areas.

A PhD is a research degree — and should only be sought by those really wanting to do research.

A Ph.D. is a sequence of academic classes coupled by research and anlysis experience, which lasts 2-4 years.

There are a lot of programs and schools that offer BA/BS-PhD programs. You will just have to check with the graduate school that you want to attend to see if they have that sort of track available for your major.