Sagan covers several topics, and focuses mainly on the possibility of extraterrestrial intelligence, the likelihood of the existence of more advanced civilizations, and their distribution in the local galaxy, and in the universe. He describes the hypothetical opinions of more advanced intelligences and their views of the Earth, as well as communication with mankind.
Sagan's work centers on the possibility of extraterrestrial intelligence, exploring the likelihood of advanced civilizations and their potential views of Earth and communication with humanity.