"Cosmos" is a book written by astronomer and science popularizer Carl Sagan, first published in 1980. The book is based on the television series of the same name, which was hosted by Sagan and aired on PBS.

The book provides a comprehensive overview of the universe and our place within it, covering topics such as the origins of the universe, the evolution of life on Earth, and the possibilities of extraterrestrial life. Throughout the book, Sagan uses vivid analogies and metaphors to make complex scientific concepts accessible to a general audience.

"Cosmos" is notable for its engaging and conversational writing style, which makes it a great introduction to science and astronomy for those with little prior knowledge. The book is also highly praised for its ability to convey Sagan's passion for science and his belief in the importance of scientific knowledge and exploration.

In addition to its popular appeal, "Cosmos" is also considered an important work of science writing, and it is widely regarded as one of the best science books of all time. If you're interested in learning more about the universe and our place within it, or if you're simply looking for a great read, "Cosmos" is definitely worth checking out.