What is this S?

[David Raleigh Arnold <dra@openguitar.com>]

What is the "S" in the directory permissions
and how do I get rid of them?  

drw-r-Sr--  3 dra dra  4096 Mar 29 09:57 files
-rw-r--r--  1 dra dra  6100 Mar 26 08:14 handout.html
-rw-r--r--  1 dra dra  5961 Mar 15 22:16 handout.html~
-rw-r--r--  1 dra dra   844 Jan  6 17:09 harmonica.html
-rw-r--r--  1 dra dra  1046 Jan  6 16:38 harmonica.html~
drw-r-Sr--  2 dra dra  4096 Aug 27  2003 images

Thanks!  daveA

-- 
When practicing tech: Don't practice the scale, practice each note.
When practicing music: Don't practice each note, practice the music.
When practicing an etude: Practice the music and each note too.

The only technical exercises for all guitarists worth a lifetime
of practice: "Dynamic Guitar Technique".  Nothing else is close.
Free download:  http://www.openguitar.com/dynamic.html    
daveA         David Raleigh Arnold          dra..at..openguitar.com