Culture is defined as an expression of society through material things and beliefs. Culture encompasses ideology, values, religion and artistic works. Subcultures are values and norms distinct from the societal majority. A variety of subcultures can exist under one overriding culture. The United States has many subcultures, ranging from Wall Street financiers to Portuguese-American fishermen. The ways of a subculture are familiar to those who belong to it.
Small societies tend to be uniform, while complex societies, such as the United States, are multicultural. A deviant subculture is one that is opposed to the values or norms the majority of people follow, often arising from economic opportunity or a lack thereof. One example of a deviant subculture is the Mafia under prohibition.
Another type of subculture is called a counterculture. These groups, though they may not be criminal in nature, defy at least one aspect of the majority culture. People who homeschool their children are considered countercultural. Competing cultures, even benign ones, tend to trigger tensions within society. This phenomenon is expressed in the phrase "culture shock." Ethnocentrism is the belief that one's culture is superior to all others. The opposite attitude is xenocentrism, which is the belief that other cultures are superior to one's own.