U+0006 "ACK" ACKNOWLEDGE Unicode Character

U+0006 "ACK" ACKNOWLEDGE is a control character originally defined in the ASCII standard as a communication protocol signal used in data transmission. It is sent by a receiving device to indicate that it has successfully received and processed a previous message or data block, serving as a positive acknowledgment to the sender. In modern contexts, this character is rarely used in visible text and is primarily encountered in low level networking or telecommunications systems, where it helps ensure reliable data flow. Its inclusion in Unicode preserves historical encoding standards while maintaining compatibility with legacy equipment and protocols.

General Properties

Code Point	U+0006
Version Added	1.1
Unicode 1.0 Name	Acknowledge
Block	Basic Latin
General Category	Control
Canonical Combining Class	Not Reordered
Bidirectional Class	Boundary Neutral
Alias	ACK (abbreviation) ACKNOWLEDGE (control)

Encodings

HTML Decimal Encoding	
HTML Hex Encoding	
UTF-8 Encoding	0x06
UTF-16 Encoding	0x0006
UTF-32 Encoding	0x00000006
C/C++/Java Escape	\u0006

Unicode Properties

NFC Quick Check	Yes
NFD Quick Check	Yes
NFKC Quick Check	Yes
NFKD Quick Check	Yes
Numeric Type	None
Numeric Value	NaN
Line Break	Combining Mark
Script	Common
Script Extensions	Common
Indic Syllabic Category	Other
Vertical Orientation	Rotated
Grapheme Cluster Break	Control
Word Break	Other
Sentence Break	Other