mysterious grey bar with symbols in it

Hi folks,

I am using vim as installed on opensuse, and have a question about it now
that I have googled for, and cannot find any definitive information about.Or
at least, any information that I can parse into something that "works for
me". The only information I've come up with, that appears to bear on
the behavior I see is stuff about folding, but I've tried turning it off (set
nofoldenable), and nothing changes. The version of vim that opensuse loads
is v7.3.831 according to the splash screen it throws up.

My question is that when I fire up vim on some file, it begins with thefile
itself just fine. But then, after a few seconds, I get a grey bar on the left
side of the screen, in which some various symbols and numbers appear. For
an example, take a look at the attached jpg. If I ever do a normal
highlight and click,to get text from one window to another, the characters
inside the grey barcome along too, and the grey bar turns into a two column
wide space in thetransfered text, which is rather annoying and is most of the
reason for myquestion here
 
What is this functionality, why would I want it, and how can I get rid of it
if in fact I don't want it after learning what it is?
 
Thanks for any help you can provide to me,
Andy