End-of-Transmission-Block character should not be confused with End-of-Text character.
End-of-Transmission-Block (ETB) is a communications control character used to indicate the end of a block of data for communications purposes. ETB is used for segmenting data into blocks when the block structure is not necessarily related to the processing function.
In ASCII, ETB is code point 23 (0x17, or in caret notation) in the C0 control code set. In EBCDIC, ETB is code point 0x26.
Unicode also includes a character for the visual representation of the character: .