People advocate for a large number and variety of topics. Some of these are clear-cut social issues that are universally agreed to be problematic and worth solving, such as human trafficking. Others—such as abortion—are much more divisive and inspire strongly-held opinions on both sides. There may never be a consensus on this latter type of issues, but intense advocacy is likely to remain. In the United States, any issue of widespread debate and deeply-divided opinion can be referred to as a social issue. The Library of Congress has assembled an extensive list of social issues in the United States, ranging from vast ones like abortion to same-sex marriage to smaller ones like hacking and academic cheating.