ASCII Characters

What Are ASCII Characters

ASCII characters is a character set of 128 characters, each with a name and an integer ID (aka Unicode Codepoint).

• The character set includes printable characters and control characters.
• Printable Characters includes digits 0 to 9, letters A to Z uppercase and lowercase, punctuations. There are 95 printable characters.
• Control Characters are used to represent tab, start text, null, escape, bell (audio alert), end of line, end of file, end of transmission, abort, etc. Control Characters have ID 0 to 31, and 127. There are 33 control characters.
• ASCII character set is identical to Unicode characters with ID from from 0 to 127 inclusive, and each char also have the same ID.
• ASCII is abbreviation for American Standard Code for Information Interchange, created in 1960s.
• The ASCII characters can be represented by 7 binary digits. So its sometimes called 7 bits ASCII.

[see Unicode Basics: Character Set, Encoding, UTF-8, Codepoint]

Printable ASCII Characters

Here's the printable ASCII characters, in the order of their ID (aka codepoint):

!"#$%&'()*+,-./
0123456789
:;<=>?@
ABCDEFGHIJKLMNOPQRSTUVWXYZ
[\]^_`
abcdefghijklmnopqrstuvwxyz
{|}~

Representation of Control Characters

Control Characters have various notations.

• By their integer ID (codepoint) in decimal. (For example, Carriage return is 13.)
• By codepoint in hexadecimal. (For example, Carriage return is 0D.)
• By standardized abbrev. (For example, Carriage return is CR.)
• By Unicode glyph. (For example, Carriage return is ␍.) [see Unicode Symbols for ASCII Control Characters ␀]
• By caret notation. (For example, Carriage return is ^M.) (Caret notation is heavily used in emacs. [see Emacs: Newline Convention CR LF])
• In programing languages, some have C escape syntax in string. (For example, Carriage return is \r.)

ASCII Table

Here's the complete ASCII table.