What is "airborn"

Airborn is a 2004 young adult novel by Kenneth Oppel. Often recognized as steampunk, the novel is set in an alternate history where the airplane has not been invented, and instead, airships are the primary form of air transportation. Additionally, the world contains fictional animal species such as flying creatures, which live their entire lives in the sky. The book takes place aboard a transoceanic luxury passenger airship, the Aurora, and is told from the perspective of its cabin boy, Matt Cruse.