A caret in the
Arial font
Caret is the name for the symbol ^ in ASCII and some other character sets. Its Unicode code point is U+005E, and its ASCII code in hexadecimal is 5E. Strictly speaking, the caret character in common use is actually referred to in the Unicode standard as the CIRCUMFLEX ACCENT; the Unicode character named CARET is actually a distinct, much less common character, at code point U+2038 (‸). There is also a combining mark, U+02C6 MODIFIER LETTER CIRCUMFLEX ACCENT, which is used when a circumflex is to be added as a diacritical mark to another letter. However, the term caret is most frequently used to refer to the first of these.
Uses and history
The caret was originally used, and continues to be, in handwritten form as a proofreading mark to indicate where a punctuation mark, word or phrase should be inserted in a document. The caret symbol is written below the line of text for a line-level punctuation mark such as a comma, or above for a higher character such as an apostrophe; the material to be inserted may be placed inside the caret, in the margin, or above the line.
The caret is also found on some typewriters, where it is used to denote a circumflex accent in languages which require it, such as French.
Most recently, the caret has found use as a symbol in computer programming languages. This usage can be traced back to ALGOL 60, which expressed the exponentiation operator as an upward-pointing arrow, intended to evoke the superscript notation common in mathematics. The up-arrow character was codified as character 5E in the original 1963 version of the ASCII standard; however, this was a short-lived placement. The 1965 ECMA-6 standard replaced the up-arrow with the currently-used caret (and the left-arrow with the underscore); two years later, the second revision of ASCII followed suit, due to pressure from international standards committees requiring the character's presence as a diacritical mark (the circumflex).
Current usage
In modern computer systems, the ASCII character set has been largely supplanted by Unicode, which supplies a wider variety of accented characters and combining marks so that the caret's function as a circumflex is no longer necessary. Its primary role is thus in computer programming languages, which commonly retain it to denote either exponentiation (e.g. AppleScript) or the bitwise exclusive or operation (e.g. C, Java). In Smalltalk, the up-arrow symbol is still used, and indicates a value to be returned from a method.
It is also used in common emoticons such as ^_^.
Other meanings
The term caret is also sometimes used in graphical user interface terminology where it means a text insertion point indicator, frequently represented by a blinking vertical bar. In this context, it may be used interchangeably with the word cursor, although the latter term is often reserved for a mouse pointer.
External links
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