There are several categories of non-fiction in the 2009 Challenge; Biography, History and Memoir are always non-fiction, for example. The General Non-Fiction category could be used to read any of those specific types of non-fiction, or something that doesn't fall into any of them.
Non-fiction is defined as an account or representation of a subject which is presented as fact. This presentation may be accurate or not; that is, it can give either a true or a false account of the subject in question. However, it is generally assumed that the authors of such accounts believe them to be truthful at the time of their composition. Note that reporting the beliefs of others in a nonfiction format is not necessarily an endorsement of the ultimate veracity of those beliefs, it is simply saying that it is true that people believe that (for such topics as mythology, religion). Nonfiction can also be written about fiction, giving information about these other works. (Source, Wikipedia)
I think high school librarian Cathy Belben does a good job of outlining the characteristics of High-Quality Non-Fiction:
1. Good non-fiction is INTERESTING.
A "good" book isn't the same for everyone, but an interesting book is any one that appeals to a particular reader's interests and holds that interest throughout the text.
2. Good non-fiction is INTRIGUING.
Good books--fiction or non-fiction, create and satisfy curiosity about a set of characters, a situation, or a topic.
3. Good non-fiction is INSIGHTFUL.
Insight is the ability to look at a topic with a unique perspective and share that perspective with readers. An insightful book shows us
something new about a topic that we hadn't thought about before.
4. Good non-fiction is INSPIRING.
This one is certainly open for debate, but the best books are those that inspire me to act. Maybe they make me want to write a letter to the editor, or maybe they make me want to start exercising or call a forgotten friend. The best books are life-altering.
5. Good non-fiction is ENTERTAINING.
What's "entertaining" obviously differs from person to person, but I consider anything entertaining that somehow affects me emotionally--primarily if
it makes me laugh, scares me, or keeps me in suspense.
6. Good non-fiction is EDUCATIONAL.
Good educational materials utilize a variety of strategies: they show us
pictures or offer anecdotes, give details about the topic, and illustrate the ideas in such a way that when we finish reading, we know something we didn't know before.
For those readers of non-fiction, we'd love to have you post what you like about non-fiction, along with an example of a book you feel is a great piece of general non-fiction.