[Samba] readable tiny odd script question

[Bob of Donelson Trophy]

I have been reviewing Louis' script
(4-setup-sernet-samba4-MEMBER-wheezy.sh) and within the following line
(310) is an odd character combination. 

if [ ${SMBPRINTING} = no ]; then
echo "==========Disable Printing ==============================="
sed -i '49a\n # disable printing completelyn load printers = non
printing = bsdn printcap name = /dev/nulln disable spoolss = yesn'^M
<<<<<<< WHAT?
 /etc/samba/smb.conf
fi 

I am using vi editor (Debian 7.7.0) and noticed "^M" at the end of the
line. This character combination appears twice within the script. Both
time as a unique font color. Here listed above and finally on the last
line of the script. In 'test' removing the character combination the
cursor responds as though this is a single character. In other words, a
single keystroke removes both characters. 

Is this a necessary character for the script to function properly? Or is
it rogue and causing some unforeseen issues? 

(I feel bad raising this question while Louis is on a holiday. Many of
us have been using his script for some time now and history indicates
that they are working scripts. And I for one really appreciate all the
work that went into them.) 

-- 

-------------------------

Bob Wooden of Donelson Trophy

615.885.2846 (main)
www.donelsontrophy.com [1]

"Everyone deserves an award!!"
 

Links:
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[1] http://www.donelsontrophy.com