Gap creationism (also known as ruin-restoration creationism, restoration creationism, or "The Gap Theory") is a form of old Earth creationism that posits that the six-day creation, as described in the Book of Genesis, involved literal 24-hour days (light being "day" and dark "night" as God specified), but that there was a gap of time between two distinct creations in the first and the second verses of Genesis, explaining many scientific observations, including the age of the Earth.