Difference between ps -ef and ps -eLf

ps -ef only prints processes, while ps -eLf prints all threads, with two columns added. For example:
[root@centos6 ~]# ps -ef | grep rsyslogd
root 1470 1 0 2011 ? 00:01:13 /sbin/rsyslogd -c 4
root 29865 28596 0 22:45 pts/5 00:00:00 grep rsyslogd
[root@centos6 ~]# ps -eLf | grep rsyslogd
root 1470 1 1470 0 5 2011 ? 00:00:00 /sbin/rsyslogd -c 4
root 1470 1 28631 0 5 Mar04 ? 00:00:04 /sbin/rsyslogd -c 4
root 1470 1 28632 0 5 Mar04 ? 00:00:01 /sbin/rsyslogd -c 4
root 1470 1 28633 0 5 Mar04 ? 00:00:04 /sbin/rsyslogd -c 4
root 1470 1 28636 0 5 Mar04 ? 00:00:00 /sbin/rsyslogd -c 4
root 29867 28596 29867 0 1 22:45 pts/5 00:00:00 grep rsyslogd
The rsyslogd process has 5 threads, so ps -ef has only one line, and ps -eLf has 5 lines.