Editing Graphic character

{{Short description|Encoded character that is associated with one or more glyphs}}
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In [[ISO/IEC 646]] (commonly known as [[ASCII]]) and related standards including [[ISO 8859]] and [[Unicode]], a '''graphic character''', also known as '''printing character''' (or '''printable 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 [[character encoding|encoded character]] that is associated with one or more [[glyph]]s.

==ISO/IEC 646==
In ISO 646, graphic characters are contained in rows 2 through 7 of the [[code]] table. However, two of the characters in these rows, namely the [[space character]] SP at row 2 column 0 and the [[delete character]]&nbsp;DEL (also called the rubout character) at row 7 column 15, require special mention.

The space is considered to be ''both'' a graphic character and a control character in ISO 646.<ref>{{cite book|author1=L.R. Henderson|author2=A.M. Mumford|title=The Computer Graphics Metafile: Butterworth Series in Computer Graphics Standards|url=https://books.google.com/books?id=O0KeBQAAQBAJ&pg=PA102|date=20 May 2014|publisher=Elsevier Science|isbn=978-1-4831-4484-9|page=102}}</ref>  It can be considered as a character with a visible form or, in contexts such as [[teleprinter]]s, a control character that advances the print head without printing a character.

The delete character is strictly a control character, not a graphic character. This is true not only in ISO 646, but also in all related{{clarify|date=February 2012}} standards including Unicode. However, many other character sets deviate from ISO 646, and as a result a graphic character might{{efn|as is the case in [[code page 437]] and related standards}} occupy the position originally reserved for the delete character.{{efn|This does not mean the delete character is absent; it just means 0x7F is overloaded, and outputting it will either print the graphical character or perform a deletion, depending on the routine used. For example in most [[BASIC]] implementations, using the [[PRINT (BASIC)|PRINT]] command with 0x7F will delete, but using [[POKE (BASIC)|POKE]] will output the graphical character.}}

==Unicode==
In Unicode, Graphic characters are those with [[Unicode character properties#General Category|General Category]] Letter, Mark, Number, Punctuation, Symbol or Zs=space. Other code points (General categories Control, Zl=line separator, Zp=paragraph separator) are Format, Control, Private Use, Surrogate, Noncharacter or Reserved (unassigned).<ref>https://www.unicode.org/versions/Unicode5.2.0/ch02.pdf#G25564 Chapter 2, table 2.3</ref>

== {{anchor|Spacing character|Non-spacing character}}Spacing and non-spacing characters ==
Most graphic characters are '''spacing characters''', which means that each instance of a spacing character has to occupy some [[area]] in a graphic representation. For a [[Teleprinter|teletype]] or a [[typewriter]] this implies moving of the carriage after typing of a character. In the context of [[text mode]] display, each spacing character occupies one rectangular character box of equal sizes. Or maybe two adjacent ones, for non-alphabetic [[CJK characters|characters of East Asian languages]]. If a text is [[font rendering|rendered]] using [[proportional font]]s, widths of character boxes are not equal, but are [[positive number|positive]].

There exist also ''non-spacing'' graphic characters. Most of [[non-spacing character]]s are ''[[wikt:modifier|modifiers]]'', also called [[combining character]]s in Unicode, such as [[diacritic]]al marks. Although non-spacing graphic characters are uncommon in traditional [[code page]]s, there are many such in Unicode. A combining character has its distinct glyph, but it applies to a character box of another character, a spacing one. In some historical systems such as [[line printer]]s this was implemented as [[overstrike]].

Note that not all modifiers are non-spacing&nbsp;– there exists [[Spacing Modifier Letters]] Unicode block.

==See also==
* [[character encoding|encoded character]]
* [[ASCII]]

== Notes ==
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== References ==
{{Reflist}}

[[Category:Character encoding]]