Though individuality is positive and natural, we all need other people in our lives, and we form alliances with others every day. One of the most basic ways to arrange human beings is into groups. Large or small, groups serve many functions. They give an individual a sense of identity, as well as meet individual needs such as the need for emotional intimacy. In some groups, we have close personal ties to the other members. Other groups are so large and impersonal that we might never get to meet the other members. Some groups work to accomplish a task, and others meet just because the members feel a personal connection to one another.
As societies modernize, the sizes and purposes of groups change. In nonindustrialized societies, few groups exist, but in large, industrialized societies, residents commonly claim membership in a wide variety of groups. Because many types of society are so different from one another, it only makes sense that groups can differ widely in importance, purpose, and prevalence depending on the society in which they exist.