Exclamation mark

From Exampleproblems

An exclamation mark (also exclamation point, and, rarely, mark of admiration or ecphoneme) is a punctuation mark. Like the full stop (or period), it marks the end of a sentence. A sentence ending in an exclamation mark is either an actual exclamation ("Wow!"), a command ("Stop!"), or is intended to be astonishing in some way ("They were the footprints of a gigantic hound!").

In typesetting or printing (and therefore when spelling text out orally), the exclamation mark is called a screamer or bang.

For use of spaces after an exclamation mark, see the discussion for the full stop.

Origins

The symbol is believed to originate from the Latin word io, an exclamation of joy. It was formed either as a digraph of the letters i and o, or as the letter i (for io) above a full stop.

Natural languages

Frequent use of the exclamation mark is common in writing in advertising. Some brands cleverly, but confusingly, contain an exclamation mark (examples include the search engine Yahoo! and the game show Jeopardy!) Some comic books, especially superhero comics of the mid-20th century, routinely use the exclamation mark instead of the period, as periods tended to disappear due to cheap printing processes. Overuse of the exclamation mark is generally considered poor writing, since it distracts the reader and reduces the mark's meaning. Some authors however, most notably the American Tom Wolfe, are known for unashamedly liberal use of the exclamation mark.

The English town of Westward Ho!, named after the novel by Charles Kingsley, is the only place name in the United Kingdom that officially contains an exclamation mark. There is a town in Quebec called Saint-Louis-du-Ha! Ha!, which officially contains two exclamation marks in its name. The titles of several musical comedies such as Oklahoma! and Oh! Calcutta! also contain exclamation marks.

The exclamation mark is also used in Chinese, Korean and Japanese.

In some languages, such as Spanish, a sentence or clause ending in an exclamation mark must also begin with an inverted exclamation mark (the same also applies to the question mark):

¿Estás loco? ¡La mataste! (English: "Are you out of your mind? You killed her!")

In Khoi, Bushmen, and the International Phonetic Alphabet, the exclamation mark is used as a letter to indicate the retroflex click sound represented as q in Zulu orthography. In Unicode this letter is properly coded as U+01C3 (ǃ) and distinguished from the common punctuation symbol U+0021 (!) to allow software to deal properly with word breaks.

There is a punctuation mark intended to combine the functions of a question mark and an exclamation mark in English called interrobang, which resembles those marks superimposed over one another ("‽") but the sequence of "?!" is used more often.

Warnings

Exclamation marks are used to emphasize a warning.

On warning signs, an exclamation mark is often used to draw attention to a warning of danger, hazards and the unexpected. These signs are common in hazardous environments or on potentially dangerous equipment. A common type of this warning is a yellow triangle with a black exclamation mark, but a white triangle with a red border is common on European road warning signs.

Fan fiction

In fan fiction, "!" is used to signify a defining quality in a character, as in romantic!Draco from Harry Potter fandom. Almost always the character in question is a canon character, and most often the quality is one that is unusual, or non-canon. Occasionally, the "!" notation will describe a physical appearance thought to trigger certain reactions, as in shirtless!Vaughn from Alias. The origin of this usage is unknown, although it is hypothesized to have originated with certain Teenage Mutant Ninja Turtles action figures, for example, "Football Player!Leonardo", "Rockstar!Raphael", and "Breakdancer!Michaelangelo".

Mathematics

In mathematics the symbol represents the factorial operation. The expression n! means "the product of the integers from 1 to n". For example, 4! (read four factorial) is 4 × 3 × 2 × 1 = 24. (0! is defined as 1, which is a neutral element in multiplication, not multiplied by anything.)

Computers

In computer programming, the exclamation mark corresponds to ASCII character 33 (21 in hexadecimal). It is therefore found in Unicode at Template:Uplusfirst0021. The inverted exclamation mark is found in ISO-8859-1, 9 and 15 at position 161 (A1_HEX) and therefore in unicode at U+00A1.

Several computer languages use "!" for various meanings, most importantly for logical negation; e.g. A ! = B means "A is not equal to B", and !A means "the logical negation of A" (also called "not A"). In this context, the exclamation is named the bang character; other programmers call it a shriek or screech. Invented in the US, it is claimed that bang is from Unix and shriek from Stanford or MIT; however, shriek is known to have been in use in the 1860s. In the BBC BASIC programming language (and BCPL) it is called a pling and is used to reference a 32-bit word (see also: Shebang).

Plings are also used in Acorn RISC OS to denote an "appfolder": a folder that when double clicked executes a program file inside called !run. Other files in the appfolder generally contain resources the application needs to run. The appfolder can be viewed as a normal folder by double-clicking with the shift key held down.

Early e-mail systems also used the exclamation point as a separator character between hostnames for routing information, usually referred to as "bang path" notation.

In the IRC protocol, a user's nickname and ident are separated by an exclamation point in the hostmask assigned to him or her by the server.

In the Geek Code, "!" is used before a letter to denote that the geek refuses to participate in the topic at hand.

When computer programs display messages that alert the user, an exclamation mark may be shown alongside it to indicate that the message is important and should be read. This often happens when an error is made, or to obtain user consent for hazardous operations such as deleting data.

Comics

In comics, a large exclamation mark is often used in the proximity of a character's head to indicate surprise.

Some comic artists regularly use an exclamation mark to stop virtually every sentence, even when a period would be more appropriate. The origin of the practice can be traced to the fact that many artists believed that the period would be lost in the printing process.

Chess

In chess notation "!" denotes a good move and "!!" an excellent move. For details see punctuation (chess).

Baseball

Exclamation points or asterisks can be used on scorecards to denote a "great defensive play." [1]

Sarcasm

In subtitles, a (!) symbol (an exclamation mark within brackets) implies that a character has made an obviously sarcastic comment eg: "That's a great idea (!)"da:Udråbstegn de:Ausrufezeichen et:Hüüumärk es:Signo de exclamación eo:Krisigno fr:Point d'exclamation he:סימן קריאה (פיסוק) nl:Uitroepteken ja:感嘆符 no:Utropstegn pl:Wykrzyknik ru:Восклицательный знак sv:Utropstecken zh:叹号