GPA. As mentioned above, your GPA is only necessary if you are a recent college graduate and do not have work experience to back you up. There are a few jobs that require a GPA, however, including engineering and finance.
However, this is a case where you’ll want to use your common sense. If you went to college for marketing and had a marketing internship your senior year, then worked as a server for the next several years, you would want to include your marketing internship.