Variable-width encoding: Difference between revisions

Revision as of 12:20, 26 June 2015

Revision as of 12:21, 26 June 2015

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UTF-16 was devised to break free of the 65,536-character limit of the original Unicode (1.x) without breaking compatibility with the 16-bit encoding. In UTF-16, singletons have the range 0000-D7FF (55296 codepoints) and E000-FFFF (8192 codepoints, 63488 in total), lead units the range D800-DBFF (1024 codepoints) and trail units the range DC00-DFFF (1024 codepoints, 2048 in total). The lead and trail units, called in Unicode terminology high surrogates and low surrogates respectively, map 1024×1024 or 1,048,576 numbers, making for a maximum of possible 1,114,112 (1,048,576 codepoints represented by high and low surrogate pairs + 63488 BMP codepoints + 2048 surrogate codepoints) codepoints in Unicode, of which 1,112,064 codepoints are valid in other encodings: UTF-8, UTF-32, where there surrogate pair ranges are not required and forbidden to be used.

==See also==

*[[wchar_t]] wide characters

{{Character encoding}}

{{use dmy dates|date=January 2012}}

{{DEFAULTSORT:Variable-Width Encoding}}

[[Category:Character encoding]]