While the basic idea of fiction as fake and non-fiction as truth hold true for all genres, there are some that fall toward the middle of the strict contrast. For example, creative non-fiction involves real events, but details are often exaggerated for dramatic effect. Memoirs can fall under both fiction and non-fiction, depending on how rooted in truth is in the story.
Many non-fiction works, while rooted basically in truth, do have a bias that means the reader or viewer should not take the story at face value. Biographies, autobiographies and documentaries are a few examples of non-fiction that often have an agenda that causes the creator to bend the truth to fit his vision.
There is also historical fiction that focuses on real events, but fictionalizes certain aspects of the story. For example, a book about the American Revolution that follows a known group of soldiers is rooted in fact. However, many things, such as internal thoughts, external dialogue and exact events, are impossible to know; these details are often crafted by the author. These blurred lines between fiction and non-fiction are easy to overlook, but typically non-fiction cites sources and does not include scenes created separately from the sources and known truth. Unless a source clearly states that it is based on actual facts, the content should be considered fictional.