Non-fiction books are written works that present factual information about real events, people, or concepts. They aim to inform, educate, or provide insights into various subjects, such as history, science, or self-help. Examples of non-fiction genres include biographies, memoirs, and textbooks. These books are often based on research and evidence, making them reliable sources for learning. Readers can explore topics like climate change, world history, or personal finance through non-fiction literature, gaining knowledge and understanding of the world around them.