The concept of 7 days of creation originates from the creation account in the book of Genesis, which is the first book of the Hebrew Bible (Old Testament) and the Christian Bible. According to this account, God created the world and everything in it in six days, and then rested on the seventh day. Here's a summary of each day of creation as described in the book of Genesis:1. Day 1: God creates light and separates it from darkness, calling the light day and the darkness night.2. Day 2: God creates the expanse or firmament to separate the waters below (seas) from the waters above (the sky or atmosphere).3. Day 3: God gathers the waters below to create dry land, and then causes vegetation—plants, trees, and vegetation—to sprout from the land.4. Day 4: God creates the sun, moon, and stars to govern the day and night, marking seasons, days, and years.5. Day 5: God creates creatures of the water and creatures of the air, including fish and birds, and commands them to be fruitful and multiply.6. Day 6: God creates land animals and then creates humans, male and female, in His own image, blessing them and giving them dominion over the rest of creation.7. Day 7: God rests from His work of creation, blessing the seventh day and making it holy.This account is foundational to both Judaism and Christianity and has been interpreted and debated in various ways throughout history. It is often understood as a theological and symbolic narrative rather than a literal scientific description of the origins of the universe.