title: How to calculate permissions for chmod command?
body: <p>After a lot of reading, I still don't understand how to use chmod. My main question is what do the numbers mean? I am new to Unix and am doing some emergency fixes on our web server and am being asked to fix the permissions for some files. I don't understand what I need to do to make the files accessible. </p>
  
  <p>Can someone provide some help here?</p>
  
  <p>EDIT: Thanks for the great answers everyone. Unfortunately, I was in a panic and didn't read them in time and we ended up losing our client.. Hard to choose any single answer but I chose the one that I understood best. </p>