coufused about ibtmp1

[victor victor]

i read 8.0/8.4 documents, the user created temp tables are in #innodb_temp dir, the parameter innodb_temp_tablespaces_dir defines the #innodb_temp dir.


but why i also see the below description about user-created temporary tables will be in ibtmp1:
InnoDB user-created temporary tables and on-disk internal temporary tables are created in a temporary tablespace file named ibtmp1 in the MySQL data directory.

https://dev.mysql.com/doc/refman/8.4/en/temporary-files.html