Young Earth Creationism (YEC) is the belief that the universe, Earth, and all life were created by a supernatural agent - typically the God of the Abrahamic scriptures - within a timeframe consistent with a literal or near-literal reading of the Genesis creation account, generally placing the age of the Earth between 6,000 and 10,000 years. YEC stands in contrast to Old Earth Creationism, which accepts mainstream geological timescales, and to evolutionary biology, which holds that life diversified over hundreds of millions of years through natural processes. The position is held primarily, though not exclusively, within certain Christian and Jewish traditions, and is advocated by organizations such as Answers in Genesis, the Institute for Creation Research, and the Creation Research Society.
YEC interpreters typically treat the six “days” (Hebrew: yom) of Genesis 1 as consecutive 24-hour periods and treat the genealogies in Genesis 5 and 11 as a reliable chronological framework. Archbishop James Ussher's 1650 calculation placing creation at 4004 BC is among the most cited historical examples of this method, though YEC advocates today may arrive at varying dates by similar reasoning. YEC also generally holds that a global flood described in Genesis 6-9 accounts for the geological and fossil record - a framework sometimes called Flood Geology.
The mainstream scientific consensus, reflected across geology, physics, cosmology, and biology, places the age of the Earth at approximately 4.54 billion years and the age of the universe at approximately 13.8 billion years. YEC proponents contest the reliability of radiometric dating, light-travel-time calculations, and stratigraphic interpretation, arguing that these methods rest on uniformitarian assumptions that a young Earth model does not accept. For the scientific consensus in detail, see Scientific Consensus on Earth and Universe Age.
YEC should be distinguished from Intelligent Design (ID), which does not commit to a young Earth or a literal Genesis reading, and from theistic evolution, which accepts mainstream timescales while affirming divine creation or guidance. It should also be distinguished from geocentrism and related positions, though some YEC advocates hold those views as well - see Heliocentrism: Religious Dissent Viewpoint.
Federal courts have ruled in a series of cases - including Edwards v. Aguillard (1987), which addressed YEC directly, and Kitzmiller v. Dover (2005), which addressed Intelligent Design - that teaching creationist alternatives as science in public schools violates the Establishment Clause of the First Amendment. The history of these disputes is covered in Young Earth Creationism - History.
A strong consensus exists across the natural sciences - including geology, astrophysics, radiometric dating, and evolutionary biology - that the Earth and universe are billions, not thousands, of years old. See Scientific Consensus on Earth and Universe Age for the scope and basis of that consensus. Consensus on this question does not itself resolve the theological or philosophical questions YEC raises, which are addressed on the viewpoint pages below.