3.4.1. Symmetric swapping format characters
The symmetric swapping format characters are used in conjunction with the class of left/right-handed pairs of characters (symmetric characters) such as parentheses. The characters thus affected are listed in Appendix G (Symmetric Swapping Characters). They indicate whether the interpretation of the term LEFT or RIGHT in the character names should be OPENING or CLOSING, respectively. They do not nest. The default state of SYMMETRIC SWAPPING may be set by a higher-level protocol or standard, such as ISO/IEC 6429. In the absence of such a protocol, the default state is ACTIVATE SYMMETRIC SWAPPING.
INHIBIT SYMMETRIC SWAPPING (U+206A)
Between this character and the following ACTIVATE SYMMETRIC SWAPPING format character (if any), the symmetric characters will be interpreted and rendered as LEFT and RIGHT.
ACTIVATE SYMMETRIC SWAPPING (U+206B)
Between this character and the following INHIBIT SYMMETRIC SWAPPING format character (if any), the symmetric characters are rendered as OPENING and CLOSING characters. This is the default state.