Here's why:
* Autobiographies are written by the subject of the book themselves, giving a personal account of their life.
* Histories are accounts of past events, often written by historians and based on research.
* Biographies are written by someone else about the subject's life.
* Secondhand biographies are a type of biography where the author relies on secondary sources (like other biographies, letters, or articles) rather than primary sources.
Let me know if you have any other questions!