Symbol Meaning

The Acknowledge symbol was designed for teletype and other communication systems. It was used to confirm the successful reception of data or messages from a remote device. As for communication protocols, Acknowledge signals successful data reception, allowing the sender to ensure the integrity and accuracy of the information delivery.

Nowadays the U+0006 symbol has become less popular, since ts functions are often replaced by other communication methods and protocols such as TCP/IP, which include built-in mechanisms for acknowledging data reception.

Like other control characters, this symbol has no visual representation and does not take up space on the screen or in typed text. There is a separate symbol in Control Pictures2400–243F representing a graphic image of the Acknowledge symbol. It shows as the ACK (Acknowledge) abbreviation — .

The symbol “Acknowledge” is included in the “C0 controls” subblock of the “Basic Latin” block and was approved as part of Unicode version 1.1 in 1993.

Text is also available in the following languages: Русский;



Unicode Name Acknowledge
Unicode Number
CSS Code
Plane 0: Basic Multilingual Plane
Unicode Block Basic Latin
Unicode Subblock C0 controls
Unicode Version 1.1 (1993)
Keyboard shortcut ^F
Type of paired mirror bracket (bidi) None
Composition Exclusion No
Case change 0006
Simple case change 0006
scripts Common
Encoding hex dec (bytes) dec binary
UTF-8 06 6 6 00000110
UTF-16BE 00 06 0 6 6 00000000 00000110
UTF-16LE 06 00 6 0 1536 00000110 00000000
UTF-32BE 00 00 00 06 0 0 0 6 6 00000000 00000000 00000000 00000110
UTF-32LE 06 00 00 00 6 0 0 0 100663296 00000110 00000000 00000000 00000000