Young Earth creationism (YEC) is the religious belief that the Universe, Earth and all life on Earth were created by direct acts of God during a relatively short period, between 5,700 and 10,000 years ago. Its primary adherents are those Christians and Jews who, using a literal interpretation of the Genesis creation narrative as a basis, believe that God created the Earth in six 24-hour days. Young Earth creationists differ from other creationists in that they believe in a strict literal interpretation of the Bible regarding the age of the Earth. In contrast, old Earth creationists interpret the six creation days (yom) of the Book of Genesis metaphorically and accept the scientifically-determined estimated ages of the Earth and of the universe.