A nonfiction book describes an event that actually took place, and is therefore not fabricated or imaginary. The nonfiction genre incorporates biographies, autobiographies, primary sources or secondary sources relating to a given event. When summarizing a nonfiction book, you must include information about its contents in a concise manner. You should provide information as to what the book is about without revealing all of the intricate details. A summary is meant to provide an overview. Therefore, in order to write a nonfiction book summary, read the book, obtain a general idea of what the book is about and state the relevant pieces of information regarding the content in chronological order.

Read the nonfiction book.

Determine the book's general idea. If the book is an autobiography or a biography, for example, you should analyze which parts of the person's life the book focuses on.

Make an outline. This will help you to organize your thoughts and write your summary more efficiently. Summaries generally consist of an introduction, a body, and a conclusion. Therefore, make three separate headings. Under the "Introduction" heading, put notes that classify the nonfiction book. Under the "Body" heading, put information regarding the general idea of the book. Under the "Conclusion" heading, make a statement about how the information presented within the book provides insight into the life of the person or the event being described.

Write the summary. Summaries are not overly long and they do not reveal information regarding the end of the book. Put all of the information from your outline into a single paragraph. At the beginning of the paragraph, introduce the type of nonfiction book, including the title and author. Then, state the general idea of the book. You can then elaborate on this concept by writing about how it provides insight into the subject of the literature. Write in the third person and do not put your own opinions into the summary.