Social movements are varied, but they do have a few shared characteristics. Generally speaking, social movements are geared toward creating, perpetuating, or stopping social or political change. The civil rights movement of the 1950s and 1960s in the United States is one example of this. It was, at least in its early stages, devoted to ending Jim Crow society in the South and to advancing social progress for African Americans. Social movements also tend to promote their cause through mass action. Today, one way this is achieved is through digital means, like online activism, but large, very public events and especially demonstrations are common to most social movements. As some sociologists have observed, social movements typically have "clearly defined opponents." Most social movements that achieve any kind of staying power are protesting something—Jim Crow, abortion, and so on. Finally, social movements tend to have some kind of organizational structure, even if this is very loose and decentralized. The civil rights movement (to use it as an example again) involved hundreds of organizations, including national ones like SNCC and the SCLC, and local ones like churches and other groups.