Believing in gods comes in more varieties than monotheism and polytheism
Theism simply means believing that at least one deity exists, but the fine print is rich. Some worship one god while admitting others exist; some worship each god in turn as supreme; some think Odin, Zeus and Indra are one deity under three names. The word itself dates only from the 17th century.
Ralph Cudworth, who lived from 1617 to 1688, coined the term, built on the Greek theos, god. For him true theists held that a perfectly conscious mind, existing from eternity, caused everything else. In everyday use theism is often set against deism: a theist accepts divine revelation, whereas a classical deist believes a creator made the world and then leaves its plan unaltered, though some deists allowed for intervention. Rejecting or not accepting belief in gods is atheism; holding that the question is unknown or unknowable is agnosticism.
Classical theism describes God as Absolute Being, with ideas such as divine simplicity at its heart. Monotheism, belief in exactly one god, underlies Christianity, Judaism and Islam. Polytheism, gods gathered into a pantheon, runs from prehistory through Egypt, Mesopotamia, Greece and Rome, and survives today in Shinto, Chinese folk religion, Taoism, Santería, most traditional African religions and neopagan movements such as Wicca and Druidry.
Modern polytheists divide into soft and hard camps. Soft polytheists may treat gods as archetypes or forces of nature, or as one deity seen through different cultures. Hard polytheists insist each god is a distinct, real being. Finer categories exist too. Henotheism accepts many gods but worships only one; Zoroastrianism is sometimes cited. Kathenotheism worships one at a time, each supreme in its turn. Monolatrism considers only one god worthy of worship, and some argue today's monotheisms started out that way, though that is disputed.
Pantheism takes another route entirely, identifying the universe itself with the divine rather than with a personal god set apart from it. Such ideas have deep roots and appear as elements within many religious traditions across thousands of years.
Source: Theism
