x0022

x0022 refers to the hexadecimal representation of the code point U+0022 in Unicode and ASCII. The character at this code point is the quotation mark, specifically the straight double quote ("). In Unicode, U+0022 is the QUOTATION MARK and is part of the basic Latin block. In ASCII, 0x22 corresponds to decimal 34, placing it among the standard printable characters.

In programming and data formats, x0022 is commonly encountered as a hex escape sequence that represents the double quote character. For example, many languages support escapes such as \x22 to insert a literal double quote inside a string. Some languages also offer a universal Unicode escape form like \u0022, which serves the same purpose in systems that distinguish Unicode escapes from simple hex escapes.

Beyond source code, the double quote character has dedicated representations in other contexts. In HTML, the quotation mark is represented by the entity " or by a numeric reference ". In JSON, double quotes must be escaped within strings to avoid prematurely terminating the string, typically as \".

Practical considerations include that the double quote is a delimiter in many languages and data formats, so proper escaping is essential when including it inside string literals. Some file systems impose restrictions on the use of quotation marks in file names, varying by platform.

See also: ASCII, Unicode, escape sequences, string literals, JSON, HTML entities.