ASCII (American Standards Code for information Interchange, US Information Interchange standard codes) is a set of character encodings based on the Latin alphabet, with a total of 128 characters, which can be stored in a single byte, equivalent to international standards ISO/IEC 646.
The ASCII specification was first released in 1967, and the last update was in 1986, which contained 33 control characters (characters with some special features but could not be displayed) and 95 characters that could be displayed.
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Double-byte Character set (Dbcs:double-byte character set), which resolves some compatibility of glyphs and ASCII for Chinese, Japanese, and Korean characters. DBCS starts with 256 code, just like ASCII. As with any code page that behaves well, the original 128 code is ASCII.
DBCS starting from 256