U+0016 "SYN" SYNCHRONOUS IDLE Unicode Character

U+0016 "SYN" SYNCHRONOUS IDLE is a control character originally defined in the ASCII standard for use in synchronous communication protocols, such as IBM's Binary Synchronous Communication (BISYNC). Its primary function is to establish and maintain synchronization between two communicating devices by being transmitted during idle periods, allowing the receiving device to align its clock with the data stream without interpreting the signal as actual data. In Unicode, it remains part of the C0 control code block, retaining its historical role in data transmission rather than serving as a printable or visible glyph.