Ansys Employee

Student is for learning for an individual. The Academic keys are purchased by an Institute at varying levels, Teaching for teaching and Research for PhD and above projects: both assume the work will be published. For commercial work (consulting or private research for a specific company) you (University) will need a Commercial licence, also purchased. 

As an aside, do NOT install Student on any machine that's running a University copy of the Ansys software. It won't end well, and you will not be popular with your IT department! 

The full (and legally correct) definitions are here