Noah built the ark at God's command in the Genesis flood narrative.
Genesis presents Noah as a righteous man who is chosen to survive a worldwide flood with his family and representatives of the animals. God gives him detailed instructions for constructing the vessel and preparing food for those aboard.
Noah is also a major figure in Judaism, Christianity, and Islam, although the accounts differ in details and emphasis. In the Qur'an, he is called Nuh and preaches to his people before the flood.
A common mix-up is treating Noah as the ark's only occupant. Genesis says that Noah's wife, his three sons, and his sons' wives also entered the ark. The story therefore links the ark with both preservation of life and the continuation of Noah's family line.