BA stands for bachelor of arts, and BS stands for bachelor of science. According to University Language Services, a BA degree requires more classes in humanities and social sciences. A BS degree concentrates on a more specific field of study in a science or vocational major.
A student pursuing a BA degree has more flexibility to take classes outside of his major than a student pursuing a BS degree. Most students who major in literature, languages, history or humanities receive a BA degree. Common BS degrees include engineering, business, agriculture and other technical fields of study. Some majors, such as psychology, biology and physics, can receive either a BA or a BS degree.