Noah is the hero of the flood narrative of Genesis 6-9: the one righteous man of a corrupt generation, commanded to build an ark, to preserve his family and the animals through a deluge that destroys all other life, and afterward to receive God's covenant, sealed by the rainbow, never again to flood the earth. As with the creation accounts, scholars find the Genesis flood story to be a composite of two interwoven sources, which accounts for its doublets, one pair of each animal in one strand, seven pairs of the clean in the other, and differing counts of the days.
The biblical flood does not stand alone. It belongs to a much older Mesopotamian tradition of a great deluge sent by the gods and survived by one favoured man in a boat. In the Atra-hasis epic and in the eleventh tablet of the Epic of Gilgamesh, the survivor, Atrahasis, or Utnapishtim, builds a vessel, rides out the flood, and sends out birds to test for dry land, releasing them exactly as Noah does. The parallels are close enough that the Genesis account is understood to draw on this common Near Eastern heritage, reworking it around the covenant with a single God rather than a quarrel among many.
The reworking is the point: what the Mesopotamian versions tell as the caprice of the gods, Genesis tells as moral judgment and merciful promise.