Many organizations use interns who are not paid for their time or their services. Often, these organizations are corporations who are allowing interns to work for them as part of their college courses; studies have shown that roughly 50 percent of college graduates have also done internships. On top of that, colleges themselves will often offer internships to their students without pay. For example, this is done at Arizona State University.
One of the potential issues with interns is that they may not have all of the same protections from discrimination, sexual harassment and the like that employees would get. The Civil Rights Act only protects actual employees who are paid, and the U.S. Equal Employment Opportunity Commission also only focuses on paid workers.