title: Find the operating system of web app's client
body: <p>I have a requirement where I have to find the operating system details of my web app's user.  If the user is running on windows it should give "Windows 7 ... Blah blah " if Linux "Ubuntu.. blah..blah OR Fedora .. .. " if Debian "whichever" version of Debian.</p>
  
  <p>Can anyone suggest how we can do it?  I had a look at <a href="https://rubygems.org/gems/sys-uname" rel="nofollow">sys-uname</a> gem.  But it is letting me know just the server side information.</p>