Using rsync for backing up my stuff on an external HDD

Quick solution, use: First make a dry run ('n') to make sure if rsync is doing right

 rsync -anPv Documents/Pictures/ /media/HDD/Pictures/

Then sync the folders

 rsync -aPv Documents/Pictures/ /media/HDD/Pictures/

If you want to skip some folders:

rsync -aPv --exclude Documents/Pictures/UNWANTED Documents/Pictures/ /media/HDD/Pictures/

This is a good place to check-out more details http://www.thegeekstuff.com/2011/01/rsync-exclude-files-and-folders/?utm_source=feedburner