string/ascii interchange

string/ascii interchangeIntroduction

1. ascii is a character encoding standard for electronic communication, which can exchange data between different computers and communication devices.

2. ascii encoding uses 7-bit or 8-bit binary numbers to represent 128 or 256 different characters.

3. in the 7-bit ascii code table, values ​​from 0 to 31 and 127 are control characters, which are not usually displayed directly on the screen, but are used internally to control text formats and communication protocols. values ​​from 32 to 126 are printable characters, including letters, numbers, and symbols.

4. when using 8-bit ascii (also known as extended ascii), the additional 128 characters (128-255) are used to represent other symbols, foreign letters, and graphic characters.