A bidirectional text contains two text directionalities, right-to-left (RTL) and left-to-right (LTR). It generally involves text containing different types of alphabets, but may also refer to boustrophedon, which is changing text direction in each row.
TeX, stylized within the system as TeX, is a typesetting system which was designed and written by computer scientist and Stanford University professor Donald Knuth and first released in 1978. TeX is a popular means of typesetting complex mathematical formulae; it has been noted as one of the most sophisticated digital typographical systems.
In ISO/IEC 646 and related standards including ISO 8859 and Unicode, a graphic character, also known as printing character, is any character intended to be written, printed, or otherwise displayed in a form that can be read by humans. In other words, it is any encoded character that is associated with one or more glyphs.
The hyphen‐ is a punctuation mark used to join words and to separate syllables of a single word. The use of hyphens is called hyphenation. Son-in-law is an example of a hyphenated word.
In writing, a space is a blank area that separates words, sentences, syllables and other written or printed glyphs (characters). Conventions for spacing vary among languages, and in some languages the spacing rules are complex. Inter-word spaces ease the reader's task of identifying words, and avoid outright ambiguities such as "now here" vs. "nowhere". They also provide convenient guides for where a human or program may start new lines.
A newline is a control character or sequence of control characters in character encoding specifications such as ASCII, EBCDIC, Unicode, etc. This character, or a sequence of characters, is used to signify the end of a line of text and the start of a new one.
In computing and typesetting, a soft hyphen or syllable hyphen, is a code point reserved in some coded character sets for the purpose of breaking words across lines by inserting visible hyphens if they fall on the line end but remain invisible within the line.
In word processing and digital typesetting, a non-breaking space, also called NBSP, required space, hard space, or fixed space, is a space character that prevents an automatic line break at its position. In some formats, including HTML, it also prevents consecutive whitespace characters from collapsing into a single space. Non-breaking space characters with other widths also exist.
In Latin script, the double hyphen⹀ is a punctuation mark that consists of two parallel hyphens. It was a development of the earlier double oblique hyphen⸗, which developed from a Central European variant of the virgule slash, originally a form of scratch comma. Similar marks are used in other scripts.
A whitespace character is a character data element that represents white space when text is rendered for display by a computer.
The Unicode Consortium and the ISO/IEC JTC 1/SC 2/WG 2 jointly collaborate on the list of the characters in the Universal Coded Character Set. The Universal Coded Character Set, most commonly called the Universal Character Set, is an international standard to map characters, discrete symbols used in natural language, mathematics, music, and other domains, to unique machine-readable data values. By creating this mapping, the UCS enables computer software vendors to interoperate, and transmit—interchange—UCS-encoded text strings from one to another. Because it is a universal map, it can be used to represent multiple languages at the same time. This avoids the confusion of using multiple legacy character encodings, which can result in the same sequence of codes having multiple interpretations depending on the character encoding in use, resulting in mojibake if the wrong one is chosen.
Many Unicode characters are used to control the interpretation or display of text, but these characters themselves have no visual or spatial representation. For example, the null character is used in C-programming application environments to indicate the end of a string of characters. In this way, these programs only require a single starting memory address for a string, since the string ends once the program reads the null character.
Writing systems that use Chinese characters also include various punctuation marks, derived from both Chinese and Western sources. Historically, judou annotations were often used to indicate the boundaries of sentences and clauses in text. The use of punctuation in written Chinese only became mandatory during the 20th century, due to Western influence. Unlike modern punctuation, judou marks were added by scholars for pedagogical purposes and were not viewed as integral to the text. Texts were therefore generally transmitted without judou. In most cases, this practice did not interfere with the interpretation of a text, although it occasionally resulted in ambiguity.
The zero-width space (), abbreviated ZWSP, is a non-printing character used in computerized typesetting to indicate word boundaries to text-processing systems for scripts that do not use explicit spacing, or after characters not followed by a visible space after which there may be a line break.
The Unicode Standard assigns various properties to each Unicode character and code point.
Sentence spacing in digital media concerns the horizontal width of the space between sentences in computer- and web-based media. Digital media allow sentence spacing variations not possible with the typewriter. Most digital fonts permit the use of a variable space or a no-break space. Some modern font specifications, such as OpenType, have the ability to automatically add or reduce space after punctuation, and users may be able to choose sentence spacing variations.
In typography, a thin space is a space character whose width is usually 1⁄5 or 1⁄6 of an em. It is used to add a narrow space, such as between nested quotation marks or to separate glyphs that interfere with one another. It is not as narrow as the hair space. It is also used in the International System of Units and in many countries as a thousands separator when writing numbers in groups of three digits, in order to facilitate reading.
General Punctuation is a Unicode block containing punctuation, spacing, and formatting characters for use with all scripts and writing systems. Included are the defined-width spaces, joining formats, directional formats, smart quotes, archaic and novel punctuation such as the interrobang, and invisible mathematical operators.
Nonprinting characters or formatting marks are characters for content designing in word processors, which are not displayed at printing. It is also possible to customize their display on the monitor. The most common nonprintable characters in word processors are pilcrow, space, nonbreaking space, tab character etc.
The Knuth–Plass algorithm is a line-breaking algorithm designed for use in Donald Knuth's typesetting program TeX. It integrates the problems of text justification and hyphenation into a single algorithm by using a discrete dynamic programming method to minimize a loss function that attempts to quantify the aesthetic qualities desired in the finished output.
