The grave accent ( ` ) ( or ) is a diacritical mark in many written languages, including Breton language, Catalan language, Corsican, Dutch language, Emilian-Romagnol, French language, West Frisian, Greek language (until 1982; see Greek diacritics), Haitian Creole, Italian language, Mohawk language, Occitan language, Portuguese, Ligurian, Scottish Gaelic, Vietnamese, Welsh language, Romansh language, and Yoruba language.
The accent mark was called , the feminine form of the adjective (), meaning "heavy" or "low in pitch". This was (loan-translated) into Latin as , which then became the English word grave.
A general rule in Italian language is that words that end with stressed -a must be marked with a grave accent. Words that end with stressed -e or -o may bear either an acute accent or a grave accent, depending on whether the final e or o sound is close vowel or open vowel, respectively. Some examples of words with a final grave accent are città ("city"), Mosè ("Moses"), and portò ("he/she/it brought/carried"). A typist who uses a keyboard without accented characters and is unfamiliar with input methods for typing accented letters sometimes use a separate grave accent or even an apostrophe instead of the proper accent. This is nonstandard but is especially common when typing capital letters: * E` or * E’ instead of È ("he/she/it is"). Other mistakes arise from the misunderstanding of apocope and elision words: the phrase un po’ ("a little"), which is the truncated version of un poco, may be mistakenly spelled as * un pò. Italian has word pairs where one has an accent marked and the other not, with different pronunciation and meaning—such as pero ("pear tree") and però ("but"), and Papa ("Pope") and papà ("dad"); the last example is also valid for Catalan language.
In Bulgarian, the grave accent sometimes appears on the vowels а, о, у, е, и, and ъ to mark stress. It most commonly appears in books for children or foreigners, and dictionaries—or to distinguish between near-: па̀ра ( pàra, "steam/vapour") and пара̀ ( parà, "cent/penny, money"), въ̀лна ( bằlna, "wool") and вълна̀ ( bǎlnà, "wave"). In a few cases (mostly on the vowels е and и), the stress mark is orthographically required to distinguish (see Disambiguation). Then, it forces the stress on the accented word-syllable instead of having a different syllable in the stress group getting accented. In turn, it changes the pronunciation and the whole meaning of the group.
Ukrainian, Rusyn language, Belarusian, and Russian language used a similar system until the first half of the 20th century. Now the main stress is preferably marked with an acute, and the role of the grave is limited to marking secondary stress in compound words (in dictionaries and linguistic literature).
In Serbo-Croatian and in Slovene language, the stressed syllable can be short or long and have a rising or falling tone. They use (in dictionaries, orthography, and grammar books, for example) four different stress marks (grave, acute, double grave, and inverted breve). The system is identical both in Latin and Cyrillic scripts.
In modern Church Slavonic, there are three stress marks (acute, grave, and circumflex), which formerly represented different types of pitch accent. There is no longer any phonetic distinction between them, only an orthographical one. The grave is typically used when the stressed vowel is the last letter of a multiletter word.
In Ligurian, the grave accent marks the accented short vowel of a word in à (sound ), è (sound ), ì (sound ) and ù (sound ). For ò, it indicates the short sound of , but may not be the stressed vowel of the word.
In Scottish Gaelic, it denotes a long vowel, such as cùis ("subject"), compared with cuir ("put"). The use of acute accents to denote the rarer close long vowels, leaving the grave accents for the open long ones, is seen in older texts, but it is no longer allowed according to the new orthographical conventions.
The grave accent represents the low tone in Mohawk language or Mohawk.
In Portuguese, the grave accent indicates the contraction of two consecutive vowels in adjacent words (crasis). For example, instead of a aquela hora ("at that hour"), one says and writes àquela hora.
In Hawaiian, the grave accent is not placed over another character but is sometimes encountered as a typographically easier substitute for the ʻokina: Hawai`i instead of Hawaiʻi.
Accents, sometimes combined with italic type, are often applied to foreign terms not commonly used in or that are not fully assimilated into English: for example, , pièce de résistance and crème brûlée.
Additionally ASCII grave accent character () was often used as surrogate of opening single quote, together with ASCII typewriter apostrophe () used as closing single quote; double quotes were sometimes substituted by two consecutive grave accents and two consecutive typewriter apostrophes (``…''). Although Unicode now provides separate characters for single and double quotes, such style is sometimes used even nowadays; examples are: output generated by some of UNIX console programs, rendering of man pages within some environments, technical documentation written long ago or written in old-school manner. However, as time goes on, such style is used less and less; and even institutions that traditionally were using that style are now abandoning it.
The Unicode standard makes dozens of letters with a grave accent available as a combining character. The older ISO-8859-1 character encoding only includes the letters à, è, ì, ò, ù, and their respective Majuscule forms. In the much older, limited 7-bit ASCII character set, the grave accent is encoded as character 96 (hexadecimal 60). Outside the US, character 96 is often replaced by accented letters. In the French ISO 646 standard, the character at this position is Micro-. Many older UK computers, such as the ZX Spectrum and BBC Micro, have the Pound Sterling symbol as character 96, though the British ISO 646 variant ultimately placed this symbol at position 35 instead.
On many computer keyboards, the grave accent is a key by itself—meant to combine with vowels as a multi-key combination or as a dead key to modify the following letter. On a US and UK QWERTY keyboard, the key is placed in the top left corner to the left of the key. On a Czech QWERTZ keyboard, the equivalent keystroke is usually mapped to .
On a Mac, to get a character such as à, the user can type and then the vowel. For example, to make à, the user can type and then , and to make À, the user can type and then . In iOS and most Android keyboards, combined characters with the grave accent are accessed by holding a finger on the vowel, which opens a menu for accents. For example, to make à, the user can tap and hold and then tap or slide to . Mac versions of OS X Mountain Lion (10.8) or newer share similar functionality to iOS; by pressing and holding a vowel key to open an accent menu, the user may click on the grave accented character or type the corresponding number key displayed.
On a system running the X Window System, to get a character such as à, the user should press followed by , then the vowel. The compose key on modern keyboards is usually mapped to a key or .
When using TeX to typeset text, the backtick character represents curly opening quotes. For example, ` is rendered as single opening curly quote () and `` is a double curly opening quote (). It also supplies the numeric ASCII value of an ASCII character wherever a number is expected.
Many of the and the programming languages Perl, PHP, and Ruby use pairs of this character to indicate command substitution, that is, substitution of the standard output from one command into a line of text defining another command. For example, the code line:
echo It is now `date`
might result, after command substitution, in the command:
echo It is now
which then, on execution, produces the output:
It is now
It is sometimes used in source code comments to indicate code, e.g.,
/* Use the `printf()` function. */
This is also the format the Markdown formatter uses to indicate code.http://daringfireball.net/projects/markdown/syntax#code Some variations of Markdown support "fenced code blocks" that span multiple lines of code, starting (and ending) with three backticks in a row (```).
Various programming and scripting languages use the backquote character: