Generally, non-fiction lacks a narrative -- in other words, a plot or story. There are exceptions, especially in post-modern literature in which authors have blurred the distinction between fiction and non-fiction. However, as a rule, works of non-fiction do not deal in narrative techniques.
There's no such thing as a single, unique non-fiction tone, but in general, non-fiction assumes a more formal, removed, academic tone. The author generally mutes his own voice and narrates from an objective, third-person point of view. Again, there are exceptions to this rule (autobiographical works, for example), but in general, non-fiction assumes a more distant, objective tone.
Some people make the false distinction that fiction is "creative" and non-fiction is not. While many common works of non-fiction (straight news stories and legal texts) have little or no creative qualities, non-fiction can also be creative and self-expressive. In fact, "creative non-fiction" is even a literary sub-genre, and includes, for example, highly stylized first-person accounts of actual events. "In Cold Blood," the Truman Capote book about a murder and homicide in the 1950s, can be considered a work of creative non-fiction.
Common examples of non-fiction include news articles, biographies, philosophical works, works of history and political texts. These examples represent a diverse range of texts, but what they have in common is that they are fundamentally designed to communicate fact -- even if the facts the address are not entirely accurate or serve a personal or political agenda.