A field guide is a book designed to help the reader identify wildlife (plants or animals) or other objects of natural occurrence (e.g. minerals). It is generally designed to be brought into the 'field' or local area where such objects exist to help distinguish between similar objects. Field guides are often designed to help users distinguish animals and plants that may be similar in appearance but are not necessarily closely related.
I did not hit her, It is not true, it is bullshit. I did not hit her, I did naaaaaaaht, Oh hi Mark.