CHMOD / UMASK /RWX 755

Linux Desktop is already popular now a day, because of this even me I  always rely using GUI "Gooey" meaning mice instead using CLI or linux terminal..
But at this time i need to go back to  my CLI bash Shell to do things as a system 
administrator of my linux system.
Here's a deeper understanding about the chmod and umask for file access privileged..(file attribution)

source:  http://www.cyberciti.biz/tips/understanding-linux-unix-umask-value-usage.html