title: How does a Perl program know where to find the file containing Perl module it uses?
body: <p>If my Perl program uses Perl modules, how will it determine where to find the file containing the module code? </p>
  
  <p>For example, if the program contains:</p>
  
  <pre><code>use MyModule1;              # Example 1
  use This::Here::MyModule2;  # Example 2
  </code></pre>
  
  <p>where will it look?</p>