Generally speaking, fellowships normally are more educational experiences that involve professional development or academic research, whereas internships are a chance to get professional experience doing regular work. Temporary jobs, on the other hand, are just short-term positions that do not provide any benefit to the employee beyond what is involved in a typical employment relationship.
Legally, the title of the experience is not relevant to deciding whether the experience is allowed to be an unpaid internship. Courts instead will look at whether the intern is the “primary beneficiary” of the experience in determining whether the organization offering the internship is required to pay the intern. Courts use a seven-factor test, explained in Question 1, to make the “primary beneficiary” determination.