What does mod - in "mod statement" - stand for?

Hi,

Could you please tell me what does mod - in "mod statement" - stand for?

"log_statement (string)

Controls which SQL statements are logged. Valid values are none, ddl,
mod, and all. (...). mod logs all ddl statements, plus data-modifying
statements such as INSERT, UPDATE, DELETE, TRUNCATE, and COPY FROM.
(...)"
[http://www.postgresql.org/docs/current/interactive/runtime-config-logging.html]

I do know about DDL, DML, DCL, which are commonly used in RBDMS,
however I ignore about MOD, even if I understand now what it means
from the documentation.  If somebody can enlighten me.

Thanks,

--
Daniel
http://www.majormode.com/