Bracket Guide, Meaning , Facts, Information and Description
- See parenthesis for an account of the rhetorical concept from which the name of the punctuation mark is derived.
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2 In computing 3 In mathematics 4 In sports 5 In mechanics and structures 6 See also |
In writing
Brackets are punctuation marks, used in pairs to set apart or interject text within other text. Types of brackets include parentheses ( ), (the singular is parenthesis) square brackets [ ], braces { }, and angle brackets 〈 〉. All these forms may be used according to typographical conventions that may vary from publication to publication and may vary even more from language to language. Some typical uses in English texts follow.
Types of brackets
Parentheses ( )
Parentheses are used to contain parenthetical (or optional, additional) material in a sentence that could be removed without destroying the meaning of the main text. For example, "George Washington (the father of his country) was not the wooden figure with wooden teeth that many think him." Indeed, such an interjection is called a parenthesis, and may also be set off with dasheses or commass. Overuse of parentheses is usually a sign of a badly structured text, unfortunately this is pretty common in the Wikipedia.
Parentheses may be used to add supplementary information, such as "Sen. Kennedy (D., Massachusetts) spoke at length".
Historically, parentheses have been used in place of the solidus in order to depict alternatives, such as "parenthesis)(parentheses".
Parentheses may also be nested (with one set inside another set (this is not commonly used in formal writing)). Sometimes square brackets will be used for the inner set of parentheses.
Any punctuation inside parentheses or other brackets is independent from the rest of the text: "Mrs. Pennyfarthing (What? Yes, that was her name!) was my landlady".
In mathematics, parentheses are used to signify a different precedence of operators. For example, 2 + 3 × 4 would be 14, since the multiplication is done before the addition. (2 + 3) × 4 is 24, because the parentheses override normal precedence, causing the addition to be done first. They are also used to set apart the argumentss to mathematical functionss. For example, f(x) is the function f applied to the variable x.
Parentheses are sometimes called round brackets, curved brackets or, colloquially, parens, or fingernails. John Lennard (in "The exploitation of parentheses in English printed verse") usefully coined the term lunula to refer specifically to the opening curved bracket, the closing curved bracket and the textual contents between.
The bracketed expression [sic] (Latin for "thus") is used to indicate errors that are "thus in the original"; a bracketed ellipsis [...] is used to indicate deleted material; bracketed comments are used to indicate when original text has been modified: "I'd like to thank [several unimportant people] and my parentals [sic] for their love, tolerance [...] and assistance [italics added]."
Square brackets are also sometimes used as parentheses within parentheses.
With the IPA, square brackets are used to indicate a phonetic transcription (as opposed to a phonemic one).
Presumably due to the similarity of the words brace and bracket (they share an etymology), many people casually treat brace is a synonym for bracket. Therefore, when it is necessary to avoid any possibility of confusion, such as in computer programming, it may be best to use the term curly bracket rather than brace. However, general usage in English favors the latter form. The term curly braces is redundant since that is the only kind of braces there are.
In computer programming, curly brackets sometime denote the beginning and ending of a sequence of statements.
Angle brackets are used in mathematics and logic to delimit ordered n-tuples.
Single and double angle brackets (〈〈, 〉〉) or pairs of the appropriate comparison operators (<<, >>) are sometimes used instead of guillemets when the proper glyphs are not available.
The mathematical or logical symbols for greater-than (>) and less-than (<), when used as such, are not punctuation marks.
For example
A superfluous semicolon may be added after the last item for uniformity of the item lines.
The endpoint adjoining the square bracket is known as closed, while the endpoint adjoining the parenthesis is known as open. If both types of brackets are the same, the entire interval may be referred to as closed or open as appropriate. Whenever infinity or negative infinity is used as an endpoint, it is always considered open and adjoined to a parenthesis.
This is used in mathematical notation, and appears in some computer programming languages. See the article Interval (mathematics) for a more complete treatment of the subject
Square brackets [ ]
Square brackets are used to enclose explanatory or missing [...] material, especially in quoted text. For example, "I appreciate it [the honor], but I must refuse." Or, "The future of psionics [See definition] is in doubt." Curly brackets or braces { }
Curly brackets (so-called in European English; North American English prefers braces) are sometimes used in prose to indicate a series of equal choices: "Select your animal {goat, sheep, cow, horse} and follow me." They are used in specialized ways in poetry and music (to mark repeats or joined lines). In mathematics they are used to delimit sets.Angle brackets or Chevrons 〈 〉
Angle brackets (〈, 〉) are often used to enclose highlighted material. Some dictionaries use angle brackets to enclose short excerpts illustrating the usage of words. True angle brackets are not available on a typical computer keyboard, so the "less than" and "greater than" symbols are used instead (<, >). These are often loosely referred to as angle brackets when used in this way. For example, the symbols < and > are often used to set apart URLs in text, such as "I found it in Wikipedia In computing
Also, in many computer languages:
Layout rules
In normal text an opening bracket is not put at the end of a line, and a closing bracket not at the beginning. However, in computer code this is often done to aid readability. For example, a bracketed list of items separated by semi-colons may be written with the brackets on separate lines, and the items, followed by the semicolon, each on one line.H1 { font-weight: bold; font-size: 12pt; line-height: 14pt }may also be written
H1 {
font-weight: bold;
font-size: 12pt;
line-height: 14pt
}
In mathematics
In addition to the use of parentheses to specify the order of operations, both parentheses and square brackets can also be used to denote an interval. The notation [a, c) is used to indicate a sequence from a to c that is inclusive of a but exclusive of c. That is, [5, 12) would be the set of all real numbers between 5 and 12, including 5 but except 12. The numbers may come as close as they like to 12, including 11.999 and so forth (with any finite number of 9s), but 12.0 is not included. In sports
In mechanics and structures
A bracket may be an inverted "L" shape, such as is usually used to hold up a shelf, or a rafter extension and its diagonal brace supporting an overhanging roof over a gable. Decorative brackets used in furniture and mantlepieces are called corbels.