Jacobs used the term early in the 1960s. Although she did not explicitly define the term social capital, her usage referred to the value of networks. Political scientist Robert Salisbury advanced the term as a critical component of interest group formation in his 1969 article "An Exchange Theory of Interest Groups" in the Midwest Journal of Political Science. Sociologist Pierre Bourdieu used the term in 1972 in his Outline of a Theory of Practice, and clarified the term some years later in contrast to cultural, economic, administrative capital, physical capital, political capital, social capital and symbolic capital. Sociologists James Coleman (1988), as well as Barry Wellman & Scot Wortley (1990), adopted Glenn Loury's 1977 definition in developing and popularising the concept. In the late 1990s, the concept gained popularity, serving as the focus of a World Bank research programme and the subject of several mainstream books, including Robert Putnam's Bowling Alone, and Putnam & Lewis Feldstein's Better Together. All of these reflections contributed remarkably to the development of the social capital concept in the following decades. The appearance of the modern social capital conceptualization is a new way to look at this debate, keeping together the importance of community to build generalized trust and the same time, the importance of individual free choice, in order to create a more cohesive society. It is for this reason that social capital generated so much interest in the academic and political world. Definitions and forms Social capital has multiple definitions, interpretations, and uses. David Halpern argues that the popularity of social capital for policymakers is linked to the concept's duality, coming because "it has a hard nosed economic feel while restating the importance of the social." For researchers, the term is popular partly due to the broad range of outcomes it can explain; the multiplicity of uses for social capital has led to a multiplicity of definitions. Social capital has been used at various times to explain superior managerial performance, the growth of entrepreneurial firms, improved performance of functionally diverse groups, the value derived from strategic alliances, and enhanced supply-chain relations. "A resource that actors derive from specific social structures and then use to pursue their interests; it is created by changes in the relationship among actors" (Baker 1990, p. 619). Early attempts to define social capital focused on the degree to which social capital serves as a resource – be it for