Sociology is the study of social rules and processes that bind, and separate people not only as individuals, but as members of associations, groups, and institutions.
A typical textbook definition of sociology calls it the study of the social lives of humans, groups and societies. Sociology is interested in our behavior as social beings; thus the sociological field of interest ranges from the analysis of short contacts between anonymous individuals on the street to the study of global social processes.
Sociology as a discipline emerged in the 19th century as an academic response to the challenge of modernity: as the world is becoming smaller and more integrated, people's experience of the world is increasingly atomized and dispersed. Sociologists hoped not only to understand what held social groups together, but also to develop an "antidote" to social disintegration.
Today sociologists research macro-structures that organize society, such as race or ethnicity, class and gender, and institutions such as the family; social processes that represent deviation from, or the breakdown of, these structures, including crime and divorce; and micro-processes such as interpersonal interactions.
Sociologists often rely on quantitative methods of social research to describe large patterns in social relationships, and in order to develop models that can help predict social change and how people will respond to social change. Other branches of sociology believe that qualitative methods -- such as focused interviews, group discussions and ethnographic methods -- allow for a better understanding of social processes. An appropriate middle ground is that both approaches are complementary, that results from each approach can fill in results from the other approaches. For example, the quantitative methods can describe the large or general patterns, while the qualitative approaches can help to understand how individuals understand or respond to those changes.
The term was coined by Auguste Comte, who hoped to unify all studies of humankind--including history, psychology and economics. His own sociological scheme was typical of the 18th century; he believed all human life had passed through the same distinct historical stages and that, if one could grasp this progress, one could prescribe the remedies for social ills.
In the end, Sociology did not replace the other social sciences, but came to be another of them, with its own particular emphases in terms of subject matter and methods. Today, Sociology studies humankind's organizations and social institutions, largely by a comparative method. It has concentrated particularly on the organization of complex industrial societies.
The Internet is of interest for sociologists in three views at least: as a tool for research, for example by using online questionnaires instead of paper ones, as a discussion platform (see 'External links' section below), and as a research topic. Sociology of the Internet in the last sense includes analysis of online communities (e.g. as found in newsgroups), virtual communities and virtual worlds organisational change catalysed through new media like the Internet, and societal change at-large in the transformation from industrial to informational society (or to information society).
Sociology has some links with social psychology, but the former is more interested in social structures and the later in social behaviors
A distinction should be made between these and forensic studies within these disciplines, particularly where anatomy is involved. These latter studies might be better named as Forensic psychology.