Ritzer introduces "nothing",a new and important concept,into her research for sociology of consumption,and conceptualizes it as the social form that,conceived and controlled by some center,is comparatively devoid of distinctive substantive content.

The different social forms of leisure culture have different cultural and social functions.

This article narrates the sociological thought of Georg Simmel, the famous sociologist of the early stage of Germany, whose thought includes the following four parts: the formal sociology, the research on small groups, the standpoint about the coordination and the conflict, and the cultural sociology.