The Unicode Character Set
Java characters are encoded using the Unicode Character Set, which is designed to support international alphabets, punctuation, and mathematical and technical symbols. Each character is stored as 16 bits, so as many as 65,536 characters are supported.
The American Standard Code for Information Interchange (ASCII) character set is supported by the first 128 Unicode characters from 0000 to 007F, which are called the controls and Basic Latin characters, as shown on the next page.
Any character from the Unicode set can be specified as a char literal in a Java program by using the following syntax: ‘\uNNNN’ where NNNN are the four hexadecimal digits that specify the Unicode encoding for the character.
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