Date-time group

Date-time group (DTG): In a message, a set of characters, usually in a prescribed format, used to express the year, the month, the day of the month, the hour of the day, the minute of the hour and the time zone (if different from Zero zone or UTC+0). The order may vary, for example 21:52 Feb 20, 2003 (UTC).

Note 1: The DTG is usually placed in the header of the message.

Note 2: The DTG may be used as a message identifier if it is unique for each message.

Note 3: The DTG may indicate either the date and time a message was dispatched by a transmitting station or the date and time it was handed into a transmission facility by a user or originator for dispatch.

Source: from Federal Standard 1037C

See also Calendar date, ISO 8601 in Internet standards.