Errors in PHP have several different types, some of which are severe and fatal (runtime errors, parse errors), others of which are relatively innocuous (Warnings and Notices). See <a href="http://php.net/manual/en/errorfunc.constants.php">http://php.net/manual/en/errorfunc.constants.php</a><div>
<br></div><div>These which you have highlighted are Notices, which usually don&#39;t mean much. The reason they are shown are because of a few PHP error handling settings <a href="http://php.net/manual/en/errorfunc.configuration.php">http://php.net/manual/en/errorfunc.configuration.php</a></div>
<div><br></div><div>Traditionally these settings are handled in php.ini. In Drupal 7, you have some control over these via the UI if you visit admin/config/development/logging<br clear="all"><div><br></div><font color="#333333">Carl Wiedemann</font><div>
<div><font color="#333333">Website design and development consulting</font></div><div><font color="#333333"><a href="mailto:carl.wiedemann@gmail.com" target="_blank">carl.wiedemann@gmail.com</a> | skype: c4rlww</font></div>
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