In punctuation, the full stop or period is the punctuation mark placed at the end of
a sentence. The full stop glyph is sometimes called a baseline dot because, typographically,
it is a dot on the baseline. This term distinguishes the baseline dot from the interpunct.
The full stop glyph is also used for other purposes. It is often used at the end of an
initial letter used to stand for a name, and is sometimes used at the end of individual
letters in an initialism. It also has multiple contexts in mathematics and computing, where
it may be called dot or point.
History The full stop symbol derives from Aristophanes
of Byzantium who invented the system of punctuation where the height of placement of a dot on
the line determined its meaning. The high dot was called a "periodos" and indicated
a finished thought or sentence, the middle dot was called a "kolon" and indicated part
of a complete thought, while the low dot was called a "telia" and also indicated part of
a complete thought. In 19th century texts both British English
and American English were consistent in their usage of the terms "period" and "full stop".
The word "period" was used as a name for what printers often called the "full point", or
the punctuation mark that was a dot on the baseline, and used in several situations.
The phrase "full stop" was only used to refer to the punctuation mark when it was used to
terminate a sentence. At some point during the 20th century, common usage diverged, with
British English adopting "full stop" as the more generic term, and American English preserving
the more traditional usage. Usage
Full stops are one of the most commonly used punctuation marks; analysis of texts indicate
that approximately half of all punctuation marks used are full stops.
Ending sentences Full stops are used to indicate the end of
sentences. Periods after initials
It is usual to use full stops after initials; A. A. Milne, George W. Bush.
Abbreviations A full stop is used after some abbreviations.
If the abbreviation ends a declaratory sentence there is no additional period immediately
following the full stop that ends the abbreviation. This is called haplography. Though two full
stops might be expected, conventionally only one is written. In the case of an interrogative
or exclamatory sentence ending with an abbreviation, a question or exclamation mark can still be
added. Abbreviations and personal titles of address
According to the Oxford A–Z of Grammar and Punctuation, "If the abbreviation includes
both the first and last letter of the abbreviated word, as in 'Mister' ["Mr"] and 'Doctor' ["Dr"],
a full stop is not used." This does not include, for example, the standard abbreviations for
titles such as Professor or Reverend, because they do not end with the last letter of the
word they are abbreviating. Among American dialects, however, the common
convention is to include the period after these abbreviations.
Acronyms and initialisms In acronyms and initialisms, full stops are
somewhat more often placed after each initial in American English than in British English,
but this depends much upon the house style of a particular writer or publisher. The American
Chicago Manual of Style now deprecates the use of full stops in acronyms.
Mathematics The full stop glyph is used in the presentation
of numbers, but in only one of two alternate styles at a time.
In the more prevalent usage in English-speaking countries it represents a decimal separator,
visually dividing whole numbers from fractional parts. The comma is then used to separate
the whole-number parts into groups of three digits each, when numbers are sufficiently
large.
1.007 1,002.007
1,002,003.007
The more prevalent usage in much of Europe, Southern Africa, and Latin America, reverses
the roles of the comma and full stop glyph, but sometimes substitutes a space for a full
stop.
1,007 1.002,007 or 1 002,007
1.002.003,007 or 1 002 003,007
In countries that use the comma as a decimal separator, the full stop is sometimes found
as a multiplication sign; for example, 5,2 . 2 = 10,4; this usage is impractical in cases
where the full stop is used as a decimal separator, hence the use of the interpunct: 5.2 · 2
= 10.4. This notation is also seen when multiplying units in science; for example, 50 km/h could
be written as 50 km·h−1. Computing
In computing, the full stop is often used as a delimiter, such as in DNS lookups, web
addresses, and file names: www.wikipedia.org
document.txt 192.168.0.1
It is used in many programming languages as an important part of the syntax. C uses it
as a means of accessing a member of a struct, and this syntax was inherited by C++ as a
means of accessing a member of a class or object. Java and Python also follow this convention.
Pascal uses it both as a means of accessing a member of a record set, a member of an object,
and after the end construct which defines the body of the program. In Erlang, Prolog,
and Smalltalk, it marks the end of a statement. In a regular expression, it represents a match
of any character. In Perl and PHP, the full stop is the string concatenation operator.
In the Haskell standard library, the full stop is the function composition operator.
In file systems, the full stop is commonly used to separate the extension of a file name
from the name of the file. RISC OS uses full stops to separate levels of the hierarchical
file system when writing path names—similar to / in Unix-based systems and \ in MS-DOS-based
systems. In Unix-like operating systems, some applications
treat files or directories that start with a full stop as hidden. This means that they
are not displayed or listed to the user by default.
In Unix-like systems and Microsoft Windows, the dot character represents the working directory
of the file system. Two dots represent the parent directory of the working directory.
Bourne shell-derived command-line interpreters, such as sh, ksh, and Bash, use the dot as
a synonym for the source command, which reads a file and executes its content in the running
interpreter. Telegraphy
The term STOP was used in telegrams in place of the full stop. The end of a sentence would
be marked by STOP, because punctuation cost extra.
Punctuation styles when quoting
The traditional convention in American English and in Canada is "aesthetic" punctuation,
or "typesetters' quotation", where full stops and commas are included inside quotation marks
even if they are not part of the quoted sentence. The style used in the UK, and to a lesser
extent in the U.S., is "logical punctuation", which stays true to the punctuation used by
the original source, placing commas and full stops inside or outside quotation marks depending
on where they were placed in the material that is being quoted. Scientific and technical
publications, including in the U.S., almost universally use it for that reason.
The aesthetic or typesetter's rule was standard in early 19th-century Britain; its application
was advocated, for example, in the influential book The King's English by Fowler and Fowler.
"Carefree" means "free from care or anxiety." "Carefree" means "free from care or anxiety".
Before the advent of mechanical type, the order of quotation marks with full stops and
commas was not given much consideration. The printing press required that the easily damaged
smallest pieces of type for the comma and full stop be protected behind the more robust
quotation marks. Typesetters' style still adheres to this older tradition in formal
writing. It is taught to American schoolchildren when they learn how to draft prose, and is
strictly observed in most books, newspapers, magazines, and journals.
References: The Chicago Manual of Style, 15th edition; Hart's Rules for Compositors and
Readers at the University Press, Oxford. Spacing after a full stop
There have been a number of practices relating to the spacing after a full stop. Some examples
are listed below: One word space. This is the current convention
in most countries that use the ISO basic Latin alphabet for published and final written work,
as well as digital media. Two word spaces. It is sometimes claimed that
the two-space convention stems from the use of the monospaced font on typewriters, but
in fact that convention replicates much earlier typography — the intent was to provide a
clear break between sentences. This spacing method was gradually replaced by the single
space convention in published print, where space is at a premium, and continues in much
digital media. One widened space. This spacing was seen in
historical typesetting practices. It has also been used in other typesetting systems such
as the Linotype machine and the TeX system. Modern computer-based digital fonts can adjust
the spacing after terminal punctuation as well, creating space slightly wider than a
standard word space. Full stops in other scripts
In some Asian languages, notably Chinese and Japanese, a small circle is used instead of
a solid dot: "。". Notably, in Taiwan, Hong Kong, and Macao usage, the full stop is written
at center height instead of on the line. In the Devanagari script, used to write Hindi
and Sanskrit among other Indian languages, a vertical line is used to mark the end of
a sentence. In Hindi, it is known as poorna viraam in Hindi and 'Daa`ri' in Bengalee.
Some Indian languages also use the full stop, such as Marathi. In Tamil it is known as "Mutrupulli",
which means End Dot. In Sinhala, it is known as kundaliya: "෴" symbol
"full stop"). Periods were later introduced into Sinhala script after the introduction
of paper due to the influence of Western languages. See also Sinhala numerals.
Urdu uses the "۔" symbol. In Thai, no symbol corresponding to the full
stop is used as terminal punctuation. A sentence is written without spaces, and a space is
typically used to mark the end of a clause or sentence.
In the Ge'ez script used to write Amharic and several other Ethiopian and Eritrean languages,
the equivalent of the full stop following a sentence is the ˈarat nettib "።" which
means "four dots". The two dots on the right are slightly ascending from the two on the
left, with space in between them. Encodings
The character is encoded at U+002E . full stop.
See also Decimal separator
Dot Sentence spacing
Terminal punctuation Notes
External links Chicago Style Q&A on one space versus two
after sentences