Asterisk
From Wikipedia, the free encyclopedia
An asterisk (*) is a typographical symbol or glyph. It is so called because it resembles a conventional image of a star (Latin astrum). Computer scientists and mathematicians often pronounce it as star (as, for example, in the A* search algorithm or C* algebra).
The asterisk derives from the need of the printers of family trees in feudal times for a symbol to indicate date of birth. The original shape was six-armed, each arm like a teardrop shooting from the center. For this reason, in some computer circles it is called a splat, perhaps due to the "squashed-bug" appearance of the asterisk on many early line printers.
Many cultures have their own unique version of the asterisk. In Japan a character with a similar use looks like an X with dots surrounding it. This mark looks like the Chinese character for rice: 米. The Arabic asterisk is six-pointed. In some fonts the asterisk is five-pointed and the Arabic star is eight-pointed.
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apostrophe ( ’ ' ) |
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spaces ( ) ( ) ( ) |
| General typography |
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ampersand ( & ) |
| Uncommon typography |
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asterism ( ⁂ ) |
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[edit] Usage
[edit] Written text
- The asterisk is used to call out a footnote, especially when there is only one on the page. Less commonly, multiple asterisks are used to denote different footnotes on a page. (i.e., *, **, ***)
- Three spaced asterisks centered on a page may represent a jump to a different scene or thought. See Horizontal rule.
- One or more asterisks may be used to strike out portions of a word to to avoid offending by using the full form of a profanity (s**t), to preserve anonymity (Peter J***), or to avoid profanation of a holy name (G*d).
- Asterisks are sometimes used instead of typographical bullets to indicate items of a list.
- Colloquially, asterisks can be used to represent *emphasis* when italics are not available
- Asterisks are used to represent ratings of movies, restaurants, etc.: see Star (classification).
A group of three asterisks arranged in a triangular formation is called an asterism.
[edit] Linguistics
[edit] Historical linguistics
- In historical linguistics, an asterisk next to a word indicates that the word is not directly attested, but has been reconstructed on the basis of other linguistic material (see also historical linguistics, comparative method).
[edit] Generativist tradition in linguistics
- In generativism, especially syntax, an asterisk next to a word or phrase indicates that the word or phrase is ungrammatical.
[edit] Computing
[edit] Computer science
In computer science, the asterisk is used in regular expressions to denote zero or more repetitions of a pattern; this use is known as the Kleene star or Kleene closure after Stephen Kleene.
In the Unified Modeling Language, the asterisk is used to denote zero to many classes.
[edit] Computer interfaces
In some computer interfaces, such as the Unix shell and Microsoft's Command prompt, the asterisk is the wildcard character and stands for any string of characters. This is also known as a wildcard symbol. A common use of the wildcard is in searching for files on a computer. For instance, if a user wished to find a document called Document 1, search terms such as Doc* and D*ment* would return this file.
In some graphical interfaces, particularly Microsoft applications, an asterisk is prepended to the current working document name shown in a window's title bar to indicate that unsaved changes exist.
In Commodore (and related) filesystems, an asterisk appearing next to a filename in a directory listing denotes an improperly closed file, commonly called a "splat file."
[edit] Adding machines and printing calculators
Some international models of adding machines and printing calculators use the asterisk to denote the total, or the terminal sum or difference of an addition or subtraction sequence, sometimes on the keyboard where the total key is marked with an asterisk and sometimes a capital T, and on the printout.
[edit] Programming languages
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:
- In some programming languages such as the C programming language, the asterisk is used to dereference or to declare a pointer variable.
- In the Common Lisp programming language, the names of global variables are conventionally set off with asterisks, *LIKE-THIS*.
- In the Fortran programming language, and in some dialects of the Pascal programming language, a double asterisk is used to signify exponentiation: 5**3 is 5*5*5 or 125.
- In the Perl programming language, the asterisk is used to refer to the typeglob of all variables with a given name.
- In the programming languages Ruby and Python, * has two specific uses. Firstly, the unary * operator applied to a list object inside a function call will expand that list into the arguments of the function call. Secondly, a parameter preceded by * in the parameter list for a function will result in any extra parameters being aggregated into a tuple (Python) or array (Ruby).
[edit] Mathematics
The asterisk has many uses in mathematics. The following list is not exhaustive.
- The complex conjugate of a complex number (though a more common notation is <math>\bar{z}</math>[1]).
- The free product of two groups.
- Infix notation for an arbitrary binary operator.
- Convolution, e.g. f ∗ g is a convolution of f with g.
- The multiplicative group of a ring, especially when the ring is a field. E.g. <math>\mathbb{C}^* = \mathbb{C}-\{0\}</math>
- An arbitrary point in some set, for example in computing Riemann sums or when contracting a simply connected group to the singleton set { ∗ }.
- The dual space of a vector space V is denoted V*.
- The combination of an indexed collection of objects into one example, e.g. the combination of all the cohomology groups Hk(X) into the cohomology ring H*(X).
- The pushforward (differential) of a smooth map f between two smooth manifolds is denoted f∗.
- The Hodge dual operator on vector spaces <math>*: A^k \rightarrow A^{n-k}</math>.
The asterisk is also often used, in all branches of mathematics, to designate a correspondence between two mathematical entities represented by a single letter — one with the asterisk and one without.
[edit] Mathematical typography
In fine mathematical typography, the Unicode character U+2217 (∗) "math asterisk" is available (HTML entity ∗). 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.
[edit] Human genetics
- In human genetics, * is used to denote that someone is a member of a haplogroup and not any of its subclades (see * (haplogroup)).
[edit] Telephony
On a Touch-Tone telephone keypad, the asterisk (called star, or less commonly, palm or sextile[2]) is one of the two special keys, and is found to the left of the zero (the other is the number sign (pound sign or hash or, less commonly, octothorp[2])). They are used to navigate menus in Touch-Tone systems such as Voice mail, or in Vertical service codes.
[edit] E-mail, Usenet, IM
- In lieu of typographical formatting denoting emphasis (e.g., commonly, italics), a word or phrase may be bracketed by asterisks *like this*, especially in e-mail or other text-based communications where multiple typefaces are not available — i.e. in plain text.
- In informal written communications, particularly those via e-mail, instant messaging, or BBS, asterisks are often used to bracket a predicate denoting the performance of an action, to indicate that the person typing is performing that action. Example: *writes an article*. Rather than a well-formed predicate in the third person singular, sometimes just the simplest form of the verb is used (e.g. *jump* or *glomp*), especially in text RPGs where unformatted text denotes speech. Compare with the usage of the colon.
- In chatrooms and instant messaging, an asterisk is often used to correct a typo. Usage varies on whether the asterisk comes before or after the correction. For example:
- Alice: What do yuo think
- Alice: *you
- Bob: Wht,
- Bob: Wha?*
Note that because Bob wishes to correct himself again, he may decide to use two asterisks to show that his first correction was in reality, not correct.
- Bob: What?**
- As in written text, asterisks may be used as bullets for list items.
[edit] Cricket
- In cricket, it signifies a total number of runs scored by a batsman without losing his wicket, e.g. 107* means '107 not out'. When written before a player's name on a scorecard, it indicates the captain.
- It is also used on television when giving a career statistic during a match. For example, 47* in a number of matches column means that the current game is the player's 47th.
[edit] Economics
- In economics, the use of an asterisk after a letter indicating a variable such as price, output, or employment indicates that the variable is at its optimal level (that which is achieved in a perfect market situation). For instance, p* is the price level p when output y is at its corresponding optimal level of y*.
- Also in international economics asterisks are commonly used to denote economic variables in a foreign country. So for example "p" is the price of the home good and "p*" is the price of the foreign good etc.*
[edit] Education
- In the GCSE examination and PSLE, A* ("A-star") is a special top grade that is distinguished from grade A.
[edit] Games
- Certain categories of character types in role-playing games are called splats, and the game supplements describing them are called splatbooks. This usage originated with the shorthand "*book" for this type of supplement to various World of Darkness games, such as Clanbook: Ventrue (for Vampire: The Masquerade) or Tribebook: Black Furies (for Werewolf: The Apocalypse), and this usage has spread to other games with similar character-type supplements. For example, Dungeons & Dragons Third Edition has had several lines of splatbooks: the "X & Y" series including Sword & Fist and Tome & Blood prior to the "3.5" revision, the "Complete X" series including Complete Warrior and Complete Divine, and the "Races of X" series including Races of Stone and Races of the Wild.
- In many MUDs and MOOs, as well as "male", "female", and other more esoteric genders, there is a gender called "splat", which uses an asterisk to replace the letters that differ in standard English gender pronouns. For example, h* is used rather than him or her. Also, asterisks are used to signify doing an action, for example, "*action*"
[edit] Baseball
- In recent years, the asterisk has come into use on scorecards to denote a "great defensive play."[3]
[edit] Competitive sports and games
- In colloquial usage, an asterisk is used to indicate that a record is somehow tainted by circumstances, which are putatively explained in a footnote supposedly referenced by the asterisk.[4] This usage arose after the 1961 baseball season in which Roger Maris of the New York Yankees broke Babe Ruth's 34-year-old single-season home run record. Because Ruth had amassed 60 home runs in a season with only 154 games, compared to Maris's 61 over 162 games, baseball commissioner Ford Frick announced that Maris' accomplishment would be recorded in the record books with an explanation (often referred to as "an asterisk" in the retelling). In fact, Major League Baseball had no official record book at the time, but the stigma remained with Maris for many years, and the concept of a real or figurative asterisk denoting less-than-official records has become widely used in sports and other competitive endeavors. A 2001 TV movie about Maris' record-breaking season was called 61* (pronounced sixty-one asterisk) in reference to the controversy.
[edit] Barry Bonds
Fans critical of Barry Bonds, who has been accused of using performance-enhancing drugs during his baseball career, invoked the asterisk notion as he approached and later broke Hank Aaron's career home run record.[5] After Bonds hit his record-breaking 756th home run on August 7, 2007, fashion designer and enterpreneur 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.
[edit] Horse Racing
- In programs distributed at race tracks, an asterisk next to a jockey's name indicates that he or she is an apprentice, and in many cases is allowed to ride at a slightly lesser weight than the other jockeys. Such a jockey is sometimes called a "bug boy." In past performances, an asterisk is also used to denote an approximate distance.
[edit] Pop Culture
- See also: Asterisk (disambiguation)
- The Red Hot Chili Peppers use an 8-pronged asterisk as their symbol.
- The popular Japanese Hip Hop/Rock group Orange Range has a song titled "*~Asterisk", which is also the first opening theme song for the popular anime Bleach.
- The fictional comic-book character, Asterix the Gaul, is a pun on Asterisk as he is the "star" of the show.[citation needed]
- In an episode of Everybody Loves Raymond, Ray Barone (portrayed by Ray Romano) recognizes that he pronounces the word "Asterisk" "Astericks". This was never corrected in future episodes but Ray Barone never spoke the word again.
- In Pat Cadigan's novel Synners, a character sees a sign that says "U B THE *" and reads it as "You Be the Ass To Risk".
- In a song by Lil Wayne called "Back On My Grizzy" from, his mixtape "Da Drought 3", he says in a line "I'm a crazy ass star like a f*cking asterisk"
- The syndicated comic Doonesbury uses a floating asterisk (referring to the name "asterisk president") wearing a Roman helmet to represent George W. Bush.
[edit] Encodings
- See also: Character encoding
The Unicode standard states that the asterisk is distinct from the Arabic five pointed star (U+066D), the asterisk operator (U+2217), and the heavy asterisk (U+2731).[6]
The symbols are compared below (the display depends on your browser's font).
| Asterisk | Heavy Asterisk | Small Asterisk | Full Width Asterisk | Open Centre Asterisk |
|---|---|---|---|---|
| * | ✱ | ﹡ | ＊ | ✲ |
| Math/Low Asterisk | Arabic star | Japanese "rice" star | Teardrop-Spoked Asterisk | Sixteen Pointed Asterisk |
|---|---|---|---|---|
| ∗ | ٭ | ※ | ✻ | ✺ |
| Unicode | Decimal | UTF-8 | HTML | |
| Asterisk | U+002A | * | 2A | |
| Small Asterisk | U+FE61 | ﹡ | EF B9 A1 | |
| Full Width Asterisk | U+FF0A | ＊ | EF BC 8A | |
| Asterisk Operator (Math Asterisk) | U+2217 | ∗ | E2 88 97 | ∗ |
| Heavy Asterisk | U+2731 | ✱ | E2 9C B1 | |
| Open Centre Asterisk | U+2732 | ✲ | E2 9C B2 | |
| Eight Spoked Asterisk | U+2733 | ✳ | E2 9C B3 | |
| Sixteen Pointed Asterisk | U+273A | ✺ | E2 9C BA | |
| Teardrop-Spoked Asterisk | U+273B | ✻ | E2 9C BB | |
| Open Centre Teardrop-Spoked Asterisk | U+273C | ✼ | E2 9C BC | |
| Heavy Teardrop-Spoked Asterisk | U+273D | ✽ | E2 9C BD | |
| Four Teardrop-Spoked Asterisk | U+2722 | ✢ | E2 9C A2 | |
| Four Balloon-Spoked Asterisk | U+2723 | ✣ | E2 9C A3 | |
| Heavy Four Balloon-Spoked Asterisk | U+2724 | ✤ | E2 9C A4 | |
| Four Club-Spoked Asterisk | U+2725 | ✥ | E2 9C A5 | |
| Heavy Teardrop-Spoked Pinwheel Asterisk | U+2743 | ❃ | E2 9D 83 | |
| Balloon-Spoked Asterisk | U+2749 | ❉ | E2 9D 89 | |
| Eight Teardrop-Spoked Propeller Asterisk | U+274A | ❊ | E2 9D 8A | |
| Heavy Eight Teardrop-Spoked Propeller Asterisk | U+274B | ❋ | E2 9D 8B | |
| Arabic star | U+066D | ٭ | D9 AD | |
| Japanese "Rice" Star | U+203B | ※ | E2 80 BB | |
| Tag Asterisk | U+E002A | 󠀪 | F3 A0 80 AA |
[edit] See also
[edit] References
- ^ http://mathworld.wolfram.com/ComplexConjugate.html
- ^ a b US patent 3920926
- ^ Baseball Almanac - Scoring Baseball: Advanced Symbols
- ^ See e.g. Allen Barra. "An Asterisk Is Very Real, Even When It's Not", New York Times, May 27, 2007.
- ^ See e.g. Michael Wilbon. "Tarnished Records Deserve an Asterisk", Washington Post, December 4, 2004, p. D10.
- ^ Detailed descriptions of the characters [The ISO Latin 1 character repertoire
- Letter Database, source for encodingsca:Asterisc
da:Asterisk de:Sternchen (Schriftzeichen) es:Asterisco eo:Asterisko eu:Izartxo fr:Astérisque hr:Zvjezdica (pravopis) he:כוכבית nl:Asterisk ja:アスタリスク no:Asterisk pl:Asterysk pt:Asterisco ru:Звёздочка (типографика) sr:Астериск sh:Asterisk fi:Asteriski sv:Asterisk tr:Yıldız işareti zh:星號
