linux – What does it mean when a file is owned by the user “system” and the group “system”? in android file system

I just trying to understand What does it mean when a file is owned by the user “system” and the group “system”? in the android file system.

In the android device file system

root@xyz:/ # ls -l cache/
drwxrwxr-x system   system            1969-12-31 17:00 SH_DIR
drwx------ system   system            2021-06-02 23:26 backup
drwxrwx--- root     root              2021-06-02 23:17 lost+found
drwxrwxrwx root     root              2021-06-08 02:12 test
drwxrwx--- system   cache             2021-06-07 05:40 recovery

For SH_DIR and backup have owned by the user “system” and the group “system”.

Thanks in advance.