link vs file

[Jeffry Killen <jekillen@xxxxxxxxxxx>]

Hello:

I am trying to get a feel for the difference
between is_link and is_file.

So I ran this code: the result is in comment block at the bottom

<?php
if(link('index.php', 'indexLink') === false)
  {
   print "link failed";
  }
else
  {
   $_linkRes = 'false';
   $_fileRes = 'false';
   if(is_link('indexLink'))
     {
      $_linkRes = 'true';
     }
   else if(is_file('indexLink'))
     {
      $_fileRes = 'true';
     }
   print 'indexLink: link; '.$_linkRes."<br>";
   print 'indexLink: file; '.$_fileRes;
  }
/*
output:
indexLink: link; false
indexLink: file; true
*/
?>

Why is it returning false for link and true for file?

This is an apache/php v 5.3x installation on Mac Yosemite.

Forgive my ignorance, but I have not worked with links up
to this point. If I load http://localhost/indexLink I get a ton
of raw code and some html rendered.

Thank you for time and attention
JK