title: Creating a directory called 'con'
body: <p>In the Ruby console, whenever I try to make a folder 'con', I get the following error:</p>
  
  <pre><code>&gt; FileUtils.mkdir_p('con/')
  
  Errno::ENOTDIR: Not a directory - con
      from C:/RailsInstaller/Ruby2.0.0/lib/ruby/2.0.0/fileutils.rb:245:in `mkdir'
      from C:/RailsInstaller/Ruby2.0.0/lib/ruby/2.0.0/fileutils.rb:245:in `fu_mkdir'
      from C:/RailsInstaller/Ruby2.0.0/lib/ruby/2.0.0/fileutils.rb:219:in `block (2 levels) in mkdir_p'
      from C:/RailsInstaller/Ruby2.0.0/lib/ruby/2.0.0/fileutils.rb:217:in `reverse_each'
      from C:/RailsInstaller/Ruby2.0.0/lib/ruby/2.0.0/fileutils.rb:217:in `block in mkdir_p'
      from C:/RailsInstaller/Ruby2.0.0/lib/ruby/2.0.0/fileutils.rb:203:in `each'
      from C:/RailsInstaller/Ruby2.0.0/lib/ruby/2.0.0/fileutils.rb:203:in `mkdir_p'
      from (irb):21
      from C:/RailsInstaller/Ruby2.0.0/bin/irb:12:in `&lt;top (required)&gt;'
      from -e:1:in `load'
      from -e:1:in `&lt;main&gt;'
  </code></pre>
  
  <p>It does not happen for other names.</p>
  
  <p>Why does this happen?</p>
  
  <p>I use Ruby 2.0.0.</p>