In law, a citation or introductory signal is a set of phrases or words used to clarify the authority (or significance) of a legal citation as it relates to a proposition. It is used in citations to present authorities and indicate how those authorities relate to propositions in statements. Legal writers use citation signals to tell readers how the citations support (or do not support) their propositions, organizing citations in a hierarchy of importance so the reader can quickly determine the relative weight of a citation. Citation signals help a reader to discern meaning or usefulness of a reference when the reference itself provides inadequate information. Citation signals have different meanings in different U.S. citation-style systems. The two most prominent citation manuals are The Bluebook: A Uniform System of Citation and the ALWD Citation Manual. Some state-specific style manuals also provide guidance on legal citation. The Bluebook citation system is the most comprehensive and the most widely used system by courts, law firms and law reviews. Use Most citation signals are placed in front of the citation to which they apply. In the paragraph the signal is "see generally", which indicates that The Bluebook: A Uniform System of Citation (18th ed. 2005) provides background information on the topic. Signals indicating support No signal When writers do not signal a citation, the cited authority states the proposition, is the source of the cited quotation or identifies an authority referred to in the text; for example, a court points out that "the proper role of the trial and appellate courts in the federal system in reviewing the size of jury verdicts is a matter of federal law" or "Bilida was prosecuted in state court for the misdemeanor offense of possessing the raccoon without a permit". e.g. This signal, an abbreviation of the Latin exempli gratia, means "for example". It tells the reader that the citation supports the proposition; although other authorities also support the proposition, their citation(s) may not be useful or necessary. This signal may be used in combination with other signals, preceded by an italicized comma. The comma after e.g., is not italicized when attached to another signal at the end (whether supportive or not), but is italicized when e.g. appears alone. Examples: Parties challenging state abortion laws have sharply disputed in some courts the contention that a purpose of these laws, when enacted, was to protect prenatal life. See,