The Oxford Companion to Food

Non-fiction is the form of any narrative, account, or other communicative work whose assertions and descriptions are understood to be factual. 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 authors of such accounts believe them to be truthful at the time of their composition or, at least, pose them to their audience as historically or empirically true. Note that reporting the beliefs of others in a non-fiction format is not necessarily an endorsement of the ultimate veracity of those beliefs, it is simply saying it is true that people believe them . Non-fiction can also be written about fiction, giving information about these other works. Non-fiction is one of the two main divisions in writing, particularly used in libraries, the other form being fiction. However, non-fiction need not be written text necessarily, since pictures and film can also purport to present a factual account of a subject.
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Reference is a relation between objects in which one object designates, or acts as a means by which to connect to or link to, another object. The... first object in this relation is said to refer to the second object. The second object – the one to which the first object refers – is called the referent of the first object. The term reference is used in many spheres of human knowledge, adopting shades of meaning particular to the contexts in which it is used. References can take on many forms, including: a thought, a sensory perception that is audible , visual , olfactory, or tactile, emotional state, relationship with other, spacetime coordinate, symbolic or alpha-numeric, a physical object or an energy projection; but, other concrete and abstract contexts exist as methods of defining references within the scope of the various fields that require an origin, point of departure, or an original form. This includes methods that intentionally hide the reference from some observers, as in cryptography. The following sections give specific usages of reference in different subjects.
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