The critical apparatus is the critical and primary source material that accompanies an edition of a text. A critical apparatus is often a by-product of textual criticism. In historical scholarship, a primary source is a document or other source of information that was created at or near the time being studied, often by the people being studied. ... Textual criticism or lower criticism is a branch of philology or bibliography that is concerned with the identification and removal of errors from texts. ...

Many editions employ a standard format for a critical apparatus, as illustrated by a line from Hamlet, which the Oxford Complete Works (1988) prints as follows:^[1] Hamlet is a tragedy by William Shakespeare, and is one of his best-known and most-quoted plays. ...

 LAERTES. Alas, then is she drowned. 

The apparatus for the line might be rendered as:^[2]

 4.7.156 Alas, then is she drowned.] HIBBARD; Alas then, is fhe drown'd? F; Alas then is fhe drownd. Q3; Alas, then, fhe is drownd. Q2; So, fhe is drownde: Q1. 

The format of the apparatus has several parts:

• The location of the variant in the text (act, scene, line number)
• The lemma, which is the portion of the text to which the note applies
• A right bracket (])
• The source from which the edition took its reading
• A list of variants, in each case followed by the source in which the variant is found, and set off with a semicolon.

To save space, frequently-cited sources are usually assigned an abbreviation called a siglum. In Shakespeare editions, F always signifies the First Folio; the second through fourth folios are referred to as F2 through F4 respectively. Similarly, Q1 is the first quarto, Q2 the second quarto, and Q3 the third. The title page of the First Folio with the famous engraved portrait of Shakespeare by Martin Droeshout The First Folio is the name given by modern scholars to the first published collection of William Shakespeares plays; its actual title is Mr. ...

In the example given, the first folio (F) and the three early quartos (Q1 to Q3) each have a different reading of the line in question. The editors have concluded that all four early sources are corrupt, and instead have adopted a reading suggested by G. R. Hibbard. Other editors of the play may choose a different reading of the line. The apparatus summarizes all of the textual evidence, allowing readers to assess for themselves whether the editor has made the best choice. Sometimes the editor will add a commentary, defending the choice made, explaining why other readings were rejected, or discussing how other editors have treated the passage.

This format has been used for critical apparatuses of Shakespeare and many other authors. In variorum editions, the apparatus is often placed at the bottom of the page. Sometimes a three-part format is employed, with the main text at the top of the page, textual variants in the middle, and the editor's commentary at the bottom. This remains the most common format for Shakespeare editions, although the Oxford Complete Works breaks with tradition by putting its critical apparatus in a separately-published volume. A Variorum is a work that collates all known variants of a text. ...

In the United States, bibliographer Fredson Bowers established a tradition of putting the critical apparatus at the back of the book, leaving the edited text clear of apparatus. This has the advantage of leaving the main text uncluttered with editorial details that may not be of interest to the general reader. However, this format is a disadvantage to scholarly readers, who are not able to see all of the textual evidence in one place.

Notes

1. ^ William Shakespeare, The Complete Works (Oxford:Oxford University Press, 1991), p. 682
2. ^ Suggested by Stanley Wells and Gary Taylor, William Shakespeare: A Textual Companion (New York: W. W. Norton & Company, 1997), p. 408.