The book offers a review of what science has to say about climate change, from 800,000 years ago to the next glaciation, including an analysis of its effects on past human societies. Critical of the IPCC's one-sided version of climate change, the book highlights the importance of natural factors in addition to the suggested anthropogenic effects. It also evaluates the role of greenhouse gases in climate change from the distant past to the present day, and presents detailed evidence of periodical changes in solar activity associated with climate changes in the past. Based on published scientific literature and written to be easily understood by non-specialists, the book includes multiple specially created illustrations supporting the scientific arguments. This one-stop reference resource is intended for graduate students and general readers with some scientific background who are interested in the climate science not well reflected in other books and IPCC reports and only available in specialized journals. It is a book designed to foster scientific debate on a question of global interest.