Double-byte characters occupy two bytes, that is, double-byte characters contain two bytes and a total of 16 bits, while Chinese characters occupy two bytes; single-byte characters only occupy one word , are English characters.
#The operating environment of this article: Windows 7 system, Dell G3 computer.
What does double byte mean?
Single byte refers to only one word, which is an English character. Double words occupy two bytes, and Chinese characters occupy two bytes.
The English word for a single byte is byte; the bit is the smallest numerical unit, and its English word is bit.
A byte contains 8 bits. Usually the ASCII code that computer beginners come into contact with is a single-byte character. Since the computer is binary, 1 bit can only be expressed as 0 or 1. , those 8 bits (generally from right to left) can be represented by different values from 0 to 127 (2 to the 8th power minus 1).
Double-byte characters contain two bytes for a total of 16 bits.
Generally, it is easy to understand that English letters are single-byte characters, while Chinese characters are double-byte characters. Because English letters, numbers, symbols, etc. can be represented by 128 different numerical values, but too many Chinese characters cannot be represented, so it needs to be expanded to double bytes.
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