You may also benefit from connecting with employers whose listings do not explicitly target graduate students. Some of these employers may be willing to consider you for their positions, or they may know of other opportunities within their organization that would be a better fit. For some it might be a central part of a job search, for others it may be more peripheral.
Employers post their jobs based on several criteria, including degree level.
Most employers visiting campus for interviews will also offer an employer presentation on campus. Many of these are open to all students. They can serve a variety of functions. If you are still exploring your options, an employer presentation can be a great place to go to hear directly from employers what an industry or career field is all about. If you have identified a job of particular interest, attending the presentation will help you prepare for interviews, and also give you a chance to network with people from the organization.