Asterisk

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*
Asterisk
Punctuation
apostrophe  '
brackets[ ]  ( )  { }  ⟨ ⟩
colon:
comma,  ،  
dash  –  —  ―
ellipsis  ...  . . .
exclamation mark!
full stop, period.
hyphen
hyphen-minus-
question mark?
quotation marks‘ ’  “ ”  ' '  " "
semicolon;
slash, stroke, solidus/  
Word dividers
interpunct·
space    
General typography
ampersand&
asterisk*
at sign@
backslash\
bullet
caret^
dagger† ‡
degree°
ditto mark
inverted exclamation mark¡
inverted question mark¿
number sign, pound, hash, octothorpe#
numero sign
obelus÷
ordinal indicatorº ª
percent, per mil% ‰
plus and minus+ −
basis point
pilcrow
prime    
section sign§
tilde~
underscore, understrike_
vertical bar, pipe, broken bar|    ¦
Intellectual property
copyright©
sound-recording copyright
registered trademark®
service mark
trademark
Uncommon typography
asterism
hedera
index, fist
interrobang
irony punctuation
lozenge
reference mark
tie
Related
In other scripts
 
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Not to be confused with Asterix.
*
Asterisk
Punctuation
apostrophe  '
brackets[ ]  ( )  { }  ⟨ ⟩
colon:
comma,  ،  
dash  –  —  ―
ellipsis  ...  . . .
exclamation mark!
full stop, period.
hyphen
hyphen-minus-
question mark?
quotation marks‘ ’  “ ”  ' '  " "
semicolon;
slash, stroke, solidus/  
Word dividers
interpunct·
space    
General typography
ampersand&
asterisk*
at sign@
backslash\
bullet
caret^
dagger† ‡
degree°
ditto mark
inverted exclamation mark¡
inverted question mark¿
number sign, pound, hash, octothorpe#
numero sign
obelus÷
ordinal indicatorº ª
percent, per mil% ‰
plus and minus+ −
basis point
pilcrow
prime    
section sign§
tilde~
underscore, understrike_
vertical bar, pipe, broken bar|    ¦
Intellectual property
copyright©
sound-recording copyright
registered trademark®
service mark
trademark
Uncommon typography
asterism
hedera
index, fist
interrobang
irony punctuation
lozenge
reference mark
tie
Related
In other scripts
Asterisks used to illustrate a section break in Alice's Adventures in Wonderland.

An asterisk (*; Late Latin: asteriscus, from Greek: ἀστερίσκος, asteriskos, "little star")[1] is a typographical symbol or glyph. It is so called because it resembles a conventional image of a star. Computer scientists and mathematicians often call it a star (as, for example, in the A* search algorithm or C*-algebra), or, more informally, splat.[2] In English, an asterisk is usually five-pointed in sans-serif typefaces, six-pointed in serif typefaces,[citation needed] and six- or eight-pointed when handwritten. It can be used as censorship. It is also used on the internet to correct one's spelling, in which case it appears before or after the correct word.

The asterisk is derived from the need of the printers of family trees in feudal times for a symbol to indicate date of birth. The original shape was seven-armed,[citation needed] each arm like a teardrop shooting from the center.

In computer science, the asterisk is commonly used as a wildcard character, or to denote pointers, repetition, or multiplication.

Usage[edit]

Typography[edit]

    I had breakfast this mroning    *morning    I prefer serial    cereal*    I like toast    don't*    I asked for bread    *no bread 

Linguistics[edit]

In linguistics, an asterisk is placed before a word or phrase to indicate that it is not used, or there are no records of it being in use. This is used in several ways depending on what is being discussed.

Historical linguistics[edit]

In historical linguistics, the asterisk marks words or phrases that are not directly recorded in texts or other media, and that are therefore reconstructed on the basis of other linguistic material (see also comparative method).

In the following example, the Proto-Germanic word ainlif is a reconstructed form.

A double asterisk indicates a form that would be expected according to a rule, but is not actually found. That is, it indicates a reconstructed form that is not found or used, and in place of which another form is found in actual usage:

Generative linguistics[edit]

In generative linguistics, especially syntax, an asterisk in front of a word or phrase indicates that the word or phrase is not used because it is ungrammatical.

An asterisk before a parenthesis indicates that the lack of the word or phrase inside is ungrammatical, while an asterisk after the opening bracket of the parenthesis indicates that the existence of the word or phrase inside is ungrammatical.

Ambiguity[edit]

Since a word marked with an asterisk could mean either "unattested" or "impossible", it is important in some contexts to distinguish these meanings. In general, authors retain asterisks for "unattested", and prefix ˣ, **, or a superscript "?" for the latter meaning.

Music[edit]

Computing[edit]

Computer science[edit]

Computer interfaces[edit]

Adding machines and printing calculators[edit]

Programming languages[edit]

Many programming languages and calculators use the asterisk as a symbol for multiplication. It also has a number of special meanings in specific languages, for instance:

Comments in computing[edit]

Main article: block comments

In the B programming language and languages that borrow syntax from it, like C, PHP, Java, or C#, comments (parts of the code not intended to be compiled into the program) are marked by an asterisk combined with the slash:

 /* Here is a comment.    The compiler will ignore it. */ 

Some Pascal-like programming languages, for example, Object Pascal, Modula-2, Modula-3, and Oberon, as well as several other languages including ML, Mathematica, AppleScript, OCaml, Standard ML, and Maple, use an asterisk combined with a parenthesis:

 (* This is a comment.    The compiler will ignore it. *) 

CSS, while not strictly a programming language, also uses the slash-star comment format.

 body {  /* This ought to make the text more readable for far-sighted people */  text-size:24pt; } 

Mathematics[edit]

The asterisk has many uses in mathematics. The following list highlights some common uses and is not exhaustive.

stand-alone
as a unary operator, denoted in prefix notation
as a unary operator, written as a subscript
as a unary operator, written as a superscript
as a binary operator, in infix notation

The asterisk is used in all branches of mathematics to designate a correspondence between two quantities denoted by the same letter – one with the asterisk and one without.

Mathematical typography[edit]

In fine mathematical typography, the Unicode character U+2217 asterisk operator (in HTML, ∗) is available. This character also appeared in the position of the regular asterisk in the PostScript symbol character set in the Symbol font included with Windows and Macintosh operating systems and with many printers. It should be used in fine typography for a large asterisk that lines up with the other mathematical operators.

Fluid Mechanics[edit]

In fluid mechanics, an asterisk in superscript is sometimes used to mean a property at sonic speed.[5]

Statistical results[edit]

In many scientific publications, the asterisk is employed as a shorthand to denote the statistical significance of results when testing hypotheses. When the likelihood that a result occurred by chance alone is below a certain level, one or more asterisks are displayed. Popular significance levels are <0.05 (*), <0.01 (**), and <0.001 (***).

Human genetics[edit]

Telephony[edit]

On a Touch-Tone telephone keypad, the asterisk (called star, or less commonly, palm or sextile)[6] is one of the two special keys (the other is the number sign (pound sign or hash or, less commonly, octothorp[6] or square)), and is found to the left of the zero. They are used to navigate menus in Touch-Tone systems such as Voice mail, or in Vertical service codes.

Economics[edit]

Education[edit]

Games[edit]

Competitive sports and games[edit]

Cricket[edit]

Barry Bonds[edit]

Fans critical of Barry Bonds, who has been accused of using performance-enhancing drugs during his baseball career, invoked the asterisk notion during the 2007 season, as he approached and later broke Hank Aaron's career home run record.[12] Opposing fans would often hold up signs bearing asterisks whenever Bonds came up to bat. After Bonds hit his record-breaking 756th home run on August 7, 2007, fashion designer and entrepreneur Marc Ecko purchased the home run ball from the fan who caught it, and ran a poll on his Web site to determine its fate. On September 26, Ecko revealed on NBC's Today show that the ball will be branded with an asterisk and donated to the Baseball Hall of Fame. The ball, marked with a die-cut asterisk, was finally delivered to the hall on July 2, 2008 after Marc Ecko unconditionally donated the artifact rather than loaning it to the hall as originally intended.

Marketing[edit]

Asterisks (or other symbols) are commonly used in advertisements to refer readers to special terms/conditions for a certain statement, commonly placed below the statement in question. For example: an advertisement for a sale may have an asterisk after the word "sale" with the date of the sale at the bottom of the advertisement, similar to the way footnotes are used.

Religious texts[edit]

Censorship[edit]

Main article: Wordfilter

It is used as censorship over all or part of a word.

Encodings[edit]

The Unicode standard states that the asterisk is distinct from:

The symbols are compared below (the display depends on your browser's font).

AsteriskAsterisk OperatorHeavy AsteriskSmall AsteriskFull Width AsteriskOpen Centre Asterisk
*
Low AsteriskArabic starEast Asian reference markTeardrop-Spoked AsteriskSixteen Pointed Asterisk
٭
NameUnicodeDecimalUTF-8HTMLDisplayed
AsteriskU+002A&#42;2A *
Small AsteriskU+FE61&#65121;EF B9 A1 
Full Width AsteriskU+FF0A&#65290;EF BC 8A 
Low AsteriskU+204E&#8270;E2 81 8E 
Two Asterisks Aligned VerticallyU+2051&#8273;E2 81 91 
Asterisk OperatorU+2217&#8727;E2 88 97&lowast;
Heavy AsteriskU+2731&#10033;E2 9C B1 
Open Centre AsteriskU+2732&#10034;E2 9C B2 
Eight Spoked AsteriskU+2733&#10035;E2 9C B3 
Sixteen Pointed AsteriskU+273A&#10042;E2 9C BA 
Teardrop-Spoked AsteriskU+273B&#10043;E2 9C BB 
Open Centre Teardrop-Spoked AsteriskU+273C&#10044;E2 9C BC 
Heavy Teardrop-Spoked AsteriskU+273D&#10045;E2 9C BD 
Four Teardrop-Spoked AsteriskU+2722&#10018;E2 9C A2 
Four Balloon-Spoked AsteriskU+2723&#10019;E2 9C A3 
Heavy Four Balloon-Spoked AsteriskU+2724&#10020;E2 9C A4 
Four Club-Spoked AsteriskU+2725&#10021;E2 9C A5 
Heavy Teardrop-Spoked Pinwheel AsteriskU+2743&#10051;E2 9D 83 
Balloon-Spoked AsteriskU+2749&#10057;E2 9D 89 
Eight Teardrop-Spoked Propeller AsteriskU+274A&#10058;E2 9D 8A 
Heavy Eight Teardrop-Spoked Propeller AsteriskU+274B&#10059;E2 9D 8B 
Arabic starU+066D&#1645;D9 AD ٭
East Asian reference markU+203B&#8251;E2 80 BB 
Tag AsteriskU+E002A&#917546;F3 A0 80 AA 󠀪

See also[edit]

References[edit]

  1. ^ ἀστερίσκος, Henry George Liddell, Robert Scott, A Greek-English Lexicon, on Perseus
  2. ^ Free On-Line Dictionary of Computing 'splat'
  3. ^ Zimmer, Ben. "The cyberpragmatics of bounding asterisks". Language Log, University of Pennsylvania. Retrieved 24 August 2013. 
  4. ^ Complex Conjugate - from Wolfram MathWorld
  5. ^ White, F. M. Fluid Mechanics, Fourth Ed. WCB McGraw Hill.
  6. ^ a b US 3920926 
  7. ^ "Scrabble Glossary". Tucson Scrabble Club. Retrieved 2012-02-06. 
  8. ^ See e.g. Allen Barra (2007-05-27). "An Asterisk is very real, even when it's not". New York Times. 
  9. ^ Baseball Almanac - Scoring Baseball: Advanced Symbols
  10. ^ Facebook.com
  11. ^ Adcouncil.org, Ad Council, August 8, 2008
  12. ^ See e.g. Michael Wilbon (2004-12-04). "Tarnished records deserve an Asterisk". Washington Post. p. D10. 
  13. ^ "Detailed descriptions of the characters (The ISO Latin 1 character repertoire)". 2006-09-20. Retrieved ~~~~~.