Need help on Linux ls command

Hi Team,
I want to know the difference in the output of the below unix commands

ls -F

ls -F I get the output with directories suffixed with a / , but some regular files suffixed with * , @ symbols. Why is it so?

[root@localhost ~]# ls -F
abc.txt          Desktop/     install.log.syslog  Public/     testfile*
accounts/        Documents/   logdata             Templates/  test.ksh*
anaconda-ks.cfg  Downloads/   LOGFILENAME         test        typescript
backup/          $file        Music/              test1       Videos/
CALNOV           filename     novcal              test123@
cc               install.log  Pictures/           test2



ls -d list only the current directory , but ls -d */  , is there any other command to list only directories.