 <p><a href="http://php.net/manual/en/function.empty.php" rel="nofollow"><em>"Determine whether a variable is considered to be empty. A variable is considered empty <strong>if it does not exist or if its value equals FALSE</strong>. empty() does not generate a warning if the variable does not exist."</em></a> </p> <blockquote> <p>Returns FALSE if var exists and has a non-empty, non-zero value. Otherwise returns TRUE.</p> <p>The following things are considered to be empty:</p> <p>"" (an empty string)</p> <p>0 (0 as an integer)</p> <p>0.0 (0 as a float)</p> <p>"0" (0 as a string)</p> <p>NULL</p> <p>FALSE</p> <p>array() (an empty array)</p> <p>$var; (a variable declared, but without a value)</p> </blockquote>