Uyghur (Arabic form), which are written from
right to left
In a script (commonly shortened to right to left or abbreviated RTL, RL-TB or R2L), writing starts from the right of the page and continues to the left, proceeding from top to bottom for new lines. Arabic, Hebrew, Persian, Pashto, Urdu, Kashmi ...
, the question mark is mirrored right-to-left from the Latin question mark. In Unicode, two encodings are available: and . (Some browsers may display the character in the previous sentence as a forward question mark due to font or text directionality issues). In addition, the
Thaana
Thaana, Taana or Tāna ( ) is the present writing system of the Maldivian language spoken in the Maldives. Thaana has characteristics of both an abugida (diacritic, vowel-killer strokes) and a true alphabet (all vowels are written), ...
script in
Dhivehi
Dhivehi, also spelled Divehi, may refer to:
*Dhivehi people, an ethnic group native to the historic region of the Maldive Islands.
*Dhivehi language, an Indo-Aryan language predominantly spoken by about 350,000 people in the Republic of Maldives
...
uses the mirrored question mark: މަރުހަބާ؟
The Arabic question mark is also used in some other right to left scripts:
N'Ko
N'Ko () is a script devised by Solomana Kante in 1949, as a modern writing system for the Mandé languages of West Africa. The term ''N'Ko'', which means ''I say'' in all Mandé languages, is also used for the Mandé literary standard written i ...
, and
Syriac Syriac may refer to:
*Syriac language, an ancient dialect of Middle Aramaic
*Sureth, one of the modern dialects of Syriac spoken in the Nineveh Plains region
* Syriac alphabet
** Syriac (Unicode block)
** Syriac Supplement
* Neo-Aramaic languages a ...
.
Hebrew
Hebrew (; ; ) is a Northwest Semitic language of the Afroasiatic language family. Historically, it is one of the spoken languages of the Israelites and their longest-surviving descendants, the Jews and Samaritans. It was largely preserved ...
and
Yiddish
Yiddish (, or , ''yidish'' or ''idish'', , ; , ''Yidish-Taytsh'', ) is a West Germanic language historically spoken by Ashkenazi Jews. It originated during the 9th century in Central Europe, providing the nascent Ashkenazi community with a ve ...
are also written right-to-left, but they use a question mark that appears on the page in the same orientation as the left-to-right question mark.
Fullwidth question mark in East Asian languages
The question mark is also used in modern writing in
Chinese
Chinese can refer to:
* Something related to China
* Chinese people, people of Chinese nationality, citizenship, and/or ethnicity
**''Zhonghua minzu'', the supra-ethnic concept of the Chinese nation
** List of ethnic groups in China, people of ...
and, to a lesser extent,
Japanese
Japanese may refer to:
* Something from or related to Japan, an island country in East Asia
* Japanese language, spoken mainly in Japan
* Japanese people, the ethnic group that identifies with Japan through ancestry or culture
** Japanese diaspor ...
. Usually it is written as
fullwidth form in Chinese and Japanese, in Unicode: .
Chinese and Japanese also have a spoken indicator of questions, 吗 (ma) and か (ka) respectively, which essentially function as a verbal question mark. Because of this, in Japanese use of the question mark is optional with か. Thus the same sentence could be written both いいですか?('May I?') or いいですか。(Still 'May I?'), but usually, the question mark is used.
In other scripts
Some other scripts have a specific question mark:
*
*
* , and
*
Stylistic variants
French usage should include a
narrow non-breaking space before the question mark. (For example, ""), whereas in the English language orthography no space is allowed in front of the question mark (e.g. "What would you like to drink?").
Typological variants of "?"
The rhetorical question mark or percontation point (see
Irony punctuation
Irony punctuation is any form of notation proposed or used to denote irony or sarcasm in text. Written English lacks a standard way to mark irony, and several forms of punctuation have been proposed. Among the oldest and most frequently atte ...
) was invented by
Henry Denham
Henry Denham was one of the outstanding England, English Printer (publisher), printers of the sixteenth century.
He was apprenticed to Richard Tottel and took up the freedom of the Stationers' Company on 30 August 1560. In 1564 he set up his own ...
in the 1580s and was used at the end of a
rhetorical question; however, it became obsolete in the 17th century. It was the reverse of an ordinary question mark, so that instead of the main opening pointing back into the sentence, it opened away from it. This character can be represented using the
reversed question mark found at Unicode as U+2E2E.
Bracketed question marks can be used for rhetorical questions, for example , in informal contexts such as
closed captioning
Closed captioning (CC) and subtitling are both processes of displaying text on a television, video screen, or other visual display to provide additional or interpretive information. Both are typically used as a transcription of the audio po ...
.
The question mark can also be used as a
meta-sign to signal uncertainty regarding what precedes it. It is usually put between brackets: . The uncertainty may concern either a superficial level (such as unsure spelling), or a deeper
truth
Truth is the property of being in accord with fact or reality.Merriam-Webster's Online Dictionarytruth 2005 In everyday language, truth is typically ascribed to things that aim to represent reality or otherwise correspond to it, such as beliefs ...
(real
meaning).
In typography, some other variants and combinations are available: "⁇," "⁈," and "⁉," are usually used for
chess annotation symbols
When annotating chess games, commentators frequently use widely recognized annotation symbols. Question marks and exclamation points that denote a move as bad or good are ubiquitous in chess literature. Some publications intended for an internati ...
; the
interrobang
The interrobang (), also known as the interabang (often represented by any of ?!, !?, ?!? or !?!), is an unconventional punctuation mark used in various written languages and intended to combine the functions of the question mark, or interro ...
, "‽," is used to combine the functions of the question mark
and the
exclamation mark
The exclamation mark, , or exclamation point (American English), is a punctuation mark usually used after an interjection or exclamation to indicate strong feelings or to show emphasis. The exclamation mark often marks the end of a sentence, f ...
, superposing these two marks.
Unicode makes available these variants:
*
*
*
*
*
*
*
*
*
Computing
In
computing
Computing is any goal-oriented activity requiring, benefiting from, or creating computing machinery. It includes the study and experimentation of algorithmic processes, and development of both hardware and software. Computing has scientific, e ...
, the question mark
character
Character or Characters may refer to:
Arts, entertainment, and media Literature
* ''Character'' (novel), a 1936 Dutch novel by Ferdinand Bordewijk
* ''Characters'' (Theophrastus), a classical Greek set of character sketches attributed to The ...
is represented by
ASCII
ASCII ( ), abbreviated from American Standard Code for Information Interchange, is a character encoding standard for electronic communication. ASCII codes represent text in computers, telecommunications equipment, and other devices. Because of ...
code 63 (0x3F hexadecimal), and is located at Unicode code-point . The full-width (double-byte) equivalent (?), is located at code-point .
In shell and scripting languages, the question mark is often utilized as a
wildcard character
In software, a wildcard character is a kind of placeholder represented by a single character, such as an asterisk (), which can be interpreted as a number of literal characters or an empty string. It is often used in file searches so the full na ...
: a symbol that can be used to substitute for any other character or characters in a
string. In particular,
filename globbing uses "?" as a substitute for any one character, as opposed to the
asterisk
The asterisk ( ), from Late Latin , from Ancient Greek , ''asteriskos'', "little star", is a typographical symbol. It is so called because it resembles a conventional image of a heraldic star.
Computer scientists and mathematicians often voc ...
, "*", which matches zero or more characters in a string. The
inverted question mark
The inverted question mark, , and inverted exclamation mark, , are punctuation marks used to begin interrogative and exclamatory sentences or clauses in Spanish and some languages which have cultural ties with Spain, such as Asturian and Wara ...
(¿) corresponds to Unicode code-point , and can be accessed from the keyboard in
Microsoft Windows
Windows is a group of several proprietary graphical operating system families developed and marketed by Microsoft. Each family caters to a certain sector of the computing industry. For example, Windows NT for consumers, Windows Server for serv ...
on the default US layout by holding down the
Alt and typing either
1 6 8 (ANSI) or
0 1 9 1 (Unicode) on the numeric keypad. In
GNOME
A gnome is a mythological creature and diminutive spirit in Renaissance magic and alchemy, first introduced by Paracelsus in the 16th century and later adopted by more recent authors including those of modern fantasy literature. Its characte ...
applications on
Linux
Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which ...
operating systems, it can be entered by typing the hexadecimal Unicode character (minus leading zeros) while holding down both
Ctrl and
Shift, I J mm.e.:
Ctrl Shift B F. In recent
XFree86
XFree86 is an implementation of the X Window System. It was originally written for Unix-like operating systems on IBM PC compatibles and was available for many other operating systems and platforms. It is free and open source software under the X ...
and
X.Org incarnations of the
X Window System
The X Window System (X11, or simply X) is a windowing system for bitmap displays, common on Unix-like operating systems.
X provides the basic framework for a GUI environment: drawing and moving windows on the display device and interacting wit ...
, it can be accessed as a compose sequence of two straight question marks, i.e. pressing
Compose ? ? yields
¿. In
classic Mac OS
Mac OS (originally System Software; retronym: Classic Mac OS) is the series of operating systems developed for the Macintosh family of personal computers by Apple Computer from 1984 to 2001, starting with System 1 and ending with Mac OS 9. The ...
and
Mac OS X
macOS (; previously OS X and originally Mac OS X) is a Unix operating system developed and marketed by Apple Inc. since 2001. It is the primary operating system for Apple's Mac (computer), Mac computers. Within the market of ...
(macOS), the key combination
Option Shift ? produces an inverted question mark.
The question mark is used in ASCII renderings of the
International Phonetic Alphabet
The International Phonetic Alphabet (IPA) is an alphabetic system of phonetic transcription, phonetic notation based primarily on the Latin script. It was devised by the International Phonetic Association in the late 19th century as a standa ...
, such as
SAMPA
__NOTOC__
The Speech Assessment Methods Phonetic Alphabet (SAMPA) is a computer-readable phonetic script using 7-bit printable ASCII characters, based on the International Phonetic Alphabet (IPA). It was originally developed in the late 1980s for ...
, in place of the
glottal stop
The glottal plosive or stop is a type of consonantal sound used in many spoken languages, produced by obstructing airflow in the vocal tract or, more precisely, the glottis. The symbol in the International Phonetic Alphabet that represents thi ...
symbol, , (which resembles "?" without the dot), and corresponds to Unicode code point .
In
computer programming
Computer programming is the process of performing a particular computation (or more generally, accomplishing a specific computing result), usually by designing and building an executable computer program. Programming involves tasks such as ana ...
, the symbol "?" has a special meaning in many
programming language
A programming language is a system of notation for writing computer programs. Most programming languages are text-based formal languages, but they may also be graphical. They are a kind of computer language.
The description of a programming ...
s. In
C-descended languages,
?
is part of the
?:
operator, which is used to evaluate simple
boolean conditions. In
C# 2.0, the
?
modifier is used to handle
nullable data types and
??
is the
null coalescing operator
The null coalescing operator (called the Logical Defined-Or operator in Perl) is a binary operator that is part of the syntax for a basic conditional expression in several programming languages, including C#, PowerShell as of version 7.0.0, Perl a ...
. In the
POSIX
The Portable Operating System Interface (POSIX) is a family of standards specified by the IEEE Computer Society for maintaining compatibility between operating systems. POSIX defines both the system- and user-level application programming interf ...
syntax for
regular expression
A regular expression (shortened as regex or regexp; sometimes referred to as rational expression) is a sequence of characters that specifies a search pattern in text. Usually such patterns are used by string-searching algorithms for "find" or ...
s, such as that used in
Perl
Perl is a family of two high-level, general-purpose, interpreted, dynamic programming languages. "Perl" refers to Perl 5, but from 2000 to 2019 it also referred to its redesigned "sister language", Perl 6, before the latter's name was offici ...
and
Python
Python may refer to:
Snakes
* Pythonidae, a family of nonvenomous snakes found in Africa, Asia, and Australia
** ''Python'' (genus), a genus of Pythonidae found in Africa and Asia
* Python (mythology), a mythical serpent
Computing
* Python (pro ...
,
?
stands for "zero or one instance of the previous subexpression", i.e. an optional element. It can also make a quantifier like
,
+
or
*
match as few characters as possible, making it lazy, e.g.
/^.*?px/
will match the substring
165px
in
165px 17px
instead of matching
165px 17px
. In certain implementations of the
BASIC
BASIC (Beginners' All-purpose Symbolic Instruction Code) is a family of general-purpose, high-level programming languages designed for ease of use. The original version was created by John G. Kemeny and Thomas E. Kurtz at Dartmouth College ...
programming language, the
?
character may be used as a shorthand for the "print" function; in others (notably the
BBC BASIC
BBC BASIC is a version of the BASIC programming language released in 1981 as the native programming language for the BBC Micro home/personal computer, providing a standardized language for a UK computer literacy project of the BBC. It was wr ...
family),
?
is used to address a single-byte memory location. In
OCaml
OCaml ( , formerly Objective Caml) is a general-purpose programming language, general-purpose, multi-paradigm programming language which extends the Caml dialect of ML (programming language), ML with object-oriented programming, object-oriented ...
, the question mark precedes the label for an optional parameter. In
Scheme A scheme is a systematic plan for the implementation of a certain idea.
Scheme or schemer may refer to:
Arts and entertainment
* ''The Scheme'' (TV series), a BBC Scotland documentary series
* The Scheme (band), an English pop band
* ''The Schem ...
, as a convention, symbol names ending in
?
are used for predicates, such as
odd?
,
null?
, and
eq?
. Similarly, in
Ruby
A ruby is a pinkish red to blood-red colored gemstone, a variety of the mineral corundum ( aluminium oxide). Ruby is one of the most popular traditional jewelry gems and is very durable. Other varieties of gem-quality corundum are called sa ...
, method names ending in
?
are used for predicates. In
Swift
Swift or SWIFT most commonly refers to:
* SWIFT, an international organization facilitating transactions between banks
** SWIFT code
* Swift (programming language)
* Swift (bird), a family of birds
It may also refer to:
Organizations
* SWIFT, ...
a type followed by
?
denotes an
option type
In programming languages (especially functional programming languages) and type theory, an option type or maybe type is a polymorphic type that represents encapsulation of an optional value; e.g., it is used as the return type of functions whic ...
;
?
is also used in "optional chaining", where if an option value is nil, it ignores the following operations. Similarly, in
Kotlin, a type followed by
?
is
nullable and functions similar to option chaining are supported. In
APL,
?
generates random numbers or a random subset of indices. In
Rust
Rust is an iron oxide, a usually reddish-brown oxide formed by the reaction of iron and oxygen in the catalytic presence of water or air moisture. Rust consists of hydrous iron(III) oxides (Fe2O3·nH2O) and iron(III) oxide-hydroxide (FeO(OH ...
, a
?
suffix on a function or method call indicates error handling. In
SPARQL
SPARQL (pronounced "sparkle" , a recursive acronym for SPARQL Protocol and RDF Query Language) is an RDF query language—that is, a semantic query language for databases—able to retrieve and manipulate data stored in Resource Description F ...
, the question mark is used to introduce variable names, such as
?name
. In
MUMPS
MUMPS ("Massachusetts General Hospital Utility Multi-Programming System"), or M, is an imperative, high-level programming language with an integrated transaction processing key–value database. It was originally developed at Massachusetts Gener ...
, it is the pattern match operator.
In many
Web browser
A web browser is application software for accessing websites. When a user requests a web page from a particular website, the browser retrieves its files from a web server and then displays the page on the user's screen. Browsers are used on ...
s and other computer programs, when converting text between encodings, it may not be possible to map some characters into the target
character set
Character encoding is the process of assigning numbers to graphical characters, especially the written characters of human language, allowing them to be stored, transmitted, and transformed using digital computers. The numerical values that ...
. In this situation it is common to replace each unmappable character with a question mark
?, inverted question mark
¿, or the Unicode
replacement character
Specials is a short Unicode block of characters allocated at the very end of the Basic Multilingual Plane, at U+FFF0–FFFF. Of these 16 code points, five have been assigned since Unicode 3.0:
*, marks start of annotated text
*, marks start ...
, usually rendered as a white question mark in a black diamond: . This commonly occurs for apostrophes and quotation marks when they are written with software that uses its own proprietary non-standard code for these characters, such as
Microsoft Office
Microsoft Office, or simply Office, is the former name of a family of client software, server software, and services developed by Microsoft. It was first announced by Bill Gates on August 1, 1988, at COMDEX in Las Vegas. Initially a marketin ...
's
"smart quotes".
The generic
URL syntax allows for a
query string
A query string is a part of a uniform resource locator (URL) that assigns values to specified parameters. A query string commonly includes fields added to a base URL by a Web browser or other client application, for example as part of an HTML, cho ...
to be appended to a resource location in a Web address so that additional information can be passed to a script; the query mark,
?
, is used to indicate the start of a query string. A query string is usually made up of a number of different field/value pairs, each separated by the
ampersand
The ampersand, also known as the and sign, is the logogram , representing the conjunction "and". It originated as a ligature of the letters ''et''—Latin for "and".
Etymology
Traditionally in English, when spelling aloud, any letter that ...
symbol,
&
, as seen in this URL:
http://www.example.com/search.php?query=testing&database=English
Here, a script on the page
search.php on the server
www.example.com is to provide a response to the query string containing the pairs
query=testing and
database=English.
Games
In
algebraic chess notation
Algebraic notation (or AN) is the standard method for recording and describing the moves in a game of chess. It is based on a system of coordinates to uniquely identify each square on the chessboard. It is used by most books, magazines, and newsp ...
, some
chess punctuation
When annotating chess games, commentators frequently use widely recognized annotation symbols. Question marks and exclamation points that denote a move as bad or good are ubiquitous in chess literature. Some publications intended for an internati ...
conventions include: "?" denotes a bad move, "??" a
blunder, "?!" a
dubious
Doubt is a mental state in which the mind remains suspended between two or more contradictory propositions, unable to be certain of any of them.
Doubt on an emotional level is indecision between belief and disbelief. It may involve uncertainty ...
move, and "!?" an interesting move.
In
Scrabble
''Scrabble'' is a word game in which two to four players score points by placing tiles, each bearing a single letter, onto a game board divided into a 15×15 grid of squares. The tiles must form words that, in crossword fashion, read left t ...
, a question mark indicates a blank tile.
Mathematics and formal logic
In
mathematics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...
, "?" commonly denotes
Minkowski's question mark function
In mathematics, the Minkowski question-mark function, denoted , is a function with unusual fractal properties, defined by Hermann Minkowski in 1904. It maps quadratic irrational numbers to rational numbers on the unit interval, via an expressio ...
. In equations, it can mean "questioned" as opposed to "defined".
*
*
*
In
linear logic
Linear logic is a substructural logic proposed by Jean-Yves Girard as a refinement of classical and intuitionistic logic, joining the dualities of the former with many of the constructive properties of the latter. Although the logic has also be ...
, the question mark denotes one of the exponential modalities that control weakening and contraction.
Medicine
A question mark is used in English medical notes to suggest a possible
diagnosis
Diagnosis is the identification of the nature and cause of a certain phenomenon. Diagnosis is used in many different disciplines, with variations in the use of logic, analytics, and experience, to determine " cause and effect". In systems engin ...
. It facilitates the recording of a doctor's impressions regarding a patient's symptoms and signs. For example, for a patient presenting with left
lower abdominal pain, a differential diagnosis might include ''?
diverticulitis
Diverticulitis, specifically colonic diverticulitis, is a gastrointestinal disease characterized by inflammation of abnormal pouches—diverticula—which can develop in the wall of the large intestine. Symptoms typically include lower abdominal ...
'' (read as "query diverticulitis").
See also
*
Exclamation mark
The exclamation mark, , or exclamation point (American English), is a punctuation mark usually used after an interjection or exclamation to indicate strong feelings or to show emphasis. The exclamation mark often marks the end of a sentence, f ...
*
High rising terminal
The high rising terminal (HRT), also known as upspeak, uptalk, or high rising intonation (HRI) is a feature of some variants of English where declarative sentences can end with a rising pitch similar to that typically found in yes-or-no questions ...
('upspeak', 'uptalk')
*
Interrobang
The interrobang (), also known as the interabang (often represented by any of ?!, !?, ?!? or !?!), is an unconventional punctuation mark used in various written languages and intended to combine the functions of the question mark, or interro ...
*
Irony mark
Irony punctuation is any form of notation proposed or used to denote irony or sarcasm in text. Written English language, English lacks a standard way to mark irony, and several forms of punctuation have been proposed. Among the oldest and most ...
*
Terminal punctuation
Terminal punctuation refers to the punctuation marks used to identify the end of a portion of text. Terminal punctuation marks are also referred to as end marks and stops.
In languages using the ISO basic Latin alphabet, terminal punctuation mar ...
*
Inquiry
An inquiry (also spelled as enquiry in British English) is any process that has the aim of augmenting knowledge, resolving doubt, or solving a problem. A theory of inquiry is an account of the various types of inquiry and a treatment of the ...
Notes
References
Bibliography
*
*
External links
* – provides an overview of question mark usage, and the differences between direct, indirect, and rhetorical questions.
{{DEFAULTSORT:Question Mark
Interrogative words and phrases
Punctuation
Typographical symbols