In Genesis's Noah's Ark story, Noah first sent out a raven to test the receding waters. Genesis 8:7 says he released it after the Ark had come to rest and the waters were decreasing.
The raven is followed by a different bird, the dove, which Noah sends out repeatedly. The dove's returns provide more specific signs about whether the land is dry, while the raven is described first in the sequence. This order is an important detail in the biblical narrative.
The question is sometimes confused because the dove is the bird most commonly remembered from artistic depictions of Noah's Ark. The dove returns with an olive leaf in a later episode, but that event does not make it the first bird released. Genesis clearly places the raven before the dove.