"Leaves of Grass" by Walt Whitman is a poetry collection first published in 1855. Beginning with just twelve poems, Whitman continuously revised and expanded this work throughout his life, eventually creating a collection of over four hundred poems. He celebrates American democracy, nature, the human body, and sensual pleasure in verse that breaks traditional rules of rhyme and meter. The book's explicit content sparked controversy and condemnation, yet it ultimately became recognized as one of the central works of American poetry.