The sociology of religion refers to religion in society. Rather than looking at the truth or proof of truth behind certain beliefs and practices, religious sociology simply looks at what religions practice, where they came from (historically), how they have changed and developed, and what are the common and universal themes among them.
That said, the basic classification system for sociology in religion is called the "church-sect typology." It is broken down into four sections:
- The church: as an institution, the church is defined as a religion that embraces religious expression in society, provides a common worldview (how to live, etc.) for its members, and does not tolerate religious competition. Examples at this level include the Catholic church, protestant churches (collectively), or Islam.
- Denominations: within many churches there often exists different denominations. Essentially, these sub-groups subscribe to one common belief (of the larger church) but disagree on smaller details and practices. Examples at this level within the protestant church include Southern Baptist, Methodist, or Presbyterian.
- Sects: sects are even smaller groups which form by breaking apart (typically) from a denomination. Often, they are formed from discontent and disagreement. Many evangelical (Protestant) Christian denominations have further divided into more specific sects.
- Cults or New Religious Movements: like sects, cults are considered new religious movements, but rather than breaking off of an existing movement, cults most often form completely independently. Rather than advocating a return to an existing "church" (or pure religion), cults claim to believe in something completely new as a result, many times, of long lost scriptures or new prophesies. There have been small cults which make headlines through mass suicides or other radical (and often horrific) displays of unity, but there are also those who consider Jehovah's Witnesses or Mormons, for example, to be cults, because they base their beliefs off of additional scriptures and modern prophesies.
Sociologists define religion according to substantive qualities (an instution with superhuman beings (Spiro)) or functional qualities (symbols that determine power and an order of existence (Geertz)).