questions relating to the ls and grep command

[Robert.Land@t-online.de (Robert Land)]

Would someone kindly explain when to use the
"ls -d" command? The --help notes this would
list the directory entries - which puzzles me
a bit because I had never thought of there
may be more than one!
Seems I have some lack in basic knowledge on
this too.

Then, when wanting ls only to plot the names
of the subdirectories in the current directory,
I key "ls -F|grep" or "ls -p|grep".
Is this the only way, and why do the -p and -F
options do not seem to differ in any way?

Additionaly when should I use "fgrep" - what
are "fixed strings"?


Robert