ASCII code comparison table

1. Introduction to ASCII code

ASCII (American Standard Code for Information Interchange, American Standard Code for Information Interchange) is a set of character encodings based on Latin letters. A total of 128 characters are included, which can be stored in one byte. It is equivalent to the international standard ISO/IEC 646. The ASCII specification was first published in 1967 and last updated in 1986.

The ASCII encoding range is 0x00-0x7F, which is 0-127 in decimal, defining 128 single-byte characters. It contains 33 control characters (characters that have some special functions but cannot be displayed) and 95 displayable characters (numbers, letters, symbols). The national standard code GB18030 and the international code Unicode are both compatible with ASCII encoding.

2.ASCII code comparison table

3.The reason for the generation of ASCII code

In the computer, all data is stored and processed Binary numbers must be used when expressing (because computers use high and low levels to represent 1 and 0 respectively). For example, 52 letters (including uppercase) like a, b, c, d and numbers such as 0 and 1 are also represented. Some commonly used symbols (such as *, #, @, etc.) are also represented by binary numbers when stored in the computer. Of course, everyone can agree on which binary numbers are used to represent which symbol. (This is (called encoding), and if everyone wants to communicate with each other without causing confusion, then everyone must use the same encoding rules. Therefore, the relevant standardization organizations in the United States introduced ASCII encoding, which uniformly stipulates which binary numbers are used to represent the above common symbols. .

The American Standard Code for Information Interchange was developed by the American National Standard Institute (ANSI) and is a standard single-byte character encoding scheme for text-based data. It was originally an American national standard and was used as a common Western character encoding standard for different computers to communicate with each other. Later, it was established as an international standard by the International Organization for Standardization (ISO), called the ISO 646 standard. Applies to all Latin script letters.

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