In publishing, a note is a brief text in which the author comments on the subject and themes of the book and names supporting citations. In the editorial production of books and documents, typographically, a note is usually several lines of text at the bottom of the page, at the end of a chapter, at the end of a volume, or a house-style typographic usage throughout the text. Notes are usually identified with superscript numbers or a symbol.

Footnotes are informational notes located at the foot of the thematically relevant page, whilst endnotes are informational notes published at the end of a chapter, the end of a volume, or the conclusion of a multi-volume book. Unlike footnotes, which require manipulating the page design (text-block and page layouts) to accommodate the additional text, endnotes are advantageous to editorial production because the textual inclusion does not alter the design of the publication. However, graphic designers of contemporary editions of the Bible often place the notes in a narrow column in the page centre, between two columns of biblical text.

In English-language typesetting, footnotes and endnotes are usually indicated with a superscript number appended to the pertinent block of text. Typographic symbols are sometimes used instead of numbers, with their traditional ordering being:

Additional typographic characters used to identify notes include the number sign (#), the Greek letter delta (Δ), the diamond-shaped lozenge (◊), the downward arrow (↓), and the manicule (☞), a hand with an extended index finger.

Footnote reference numbers ("cues") in the body text of a page should be placed at the end of a sentence if possible, after the final punctuation. This minimizes the interruption of the flow of reading and allows the reader to absorb a complete sentence-idea before having their attention redirected to the content of the note.

The cue is placed after any punctuation (normally after the closing point of a sentence). ... Notes cued in the middle of a sentence are a distraction to the reader, and cues are best located at the end of sentences.

Notes are most often used as an alternative to long explanations, citations, comments, or annotations that can be distracting to readers. Most literary style guidelines (including the Modern Language Association and the American Psychological Association) recommend limited use of foot- and endnotes. However, publishers often encourage note references instead of parenthetical references. Aside from use as a bibliographic element, notes are used for additional information, qualification, or explanation that might be too digressive for the main text. Footnotes are heavily utilized in academic institutions to support claims made in academic essays covering myriad topics.

In particular, footnotes are the normal form of citation in historical journals. This is due, firstly, to the fact that the most important references are often to archive sources or interviews that do not readily fit standard formats, and secondly, to the fact that historians expect to see the exact nature of the evidence that is being used at each stage.