U00000003

U00000003 is a code point designation that corresponds to the control character U+0003 in the Unicode standard and ASCII frameworks. In decimal, it is 3; in hexadecimal, 0x03. It is a non-printable character used in telecommunication protocols and data streams.

Historical context: During early computing and teletype communications, ETX was used to indicate the end of a text block or to terminate a transmission. It was part of the set of ASCII control codes defined by the ASCII standard first published in 1963.

Encoding and representation: In Unicode, U+0003 is categorized as a Cc (control) character. In UTF-8, it is encoded as a single byte 0x03. In modern software, encountering the character usually yields no visible glyph; it may be interpreted by software as a control signal or be ignored/stripped in text rendering.

Usage: ETX can appear in communication protocols, data framing, and scripting environments where explicit termination is required. Because it is non-printable, its presence is typically meaningful only to parsers, protocols, or software that handle control characters.

See also: End of Text (ETX), ASCII control codes, U+0003.

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