What does it mean when asked on An employment app. Major/course of study?

When an app asks for your major/course of study, they want you to list the educational focus you pursued in college or university. A "major" is the educational focus that is, or will be, listed on your university diploma. For example, if you went (or are going) to college to study math, under "major/course of study," you would list "mathematics." If you have graduated, it is also helpful to list what sort of a diploma you received, i.e. "B.A. in Mathematics."