title: Difference between using "chmod a+x" and "chmod 755"
body: <p>This may sound silly, but I have a file/ script that need to run and in order to do it I must change it to become executable. I would want to use either <code>chmod a+x</code> or <code>chmod 755</code>. But is there a difference between using <code>chmod a+x</code> and <code>chmod 755</code>?</p>