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Hello you wonderful coders you. I've been staring at this line of code (line 74 highlighted below) for a while in m_template.php, and want to share what it's doing. function getAlerts() { $data = ''; foreach($this->alertTypes as $alert) { if (isset($_SESSION[$alert])) { foreach($_SESSION[$alert] as $value) { $data .= '<li class="'. $alert .'">' . $value . '</li>'; } unset($_SESSION[$alert]); } } return $data; } The unset is here so that the next time a user clicks the submit button, the $_SESSION variable will have a clean slate (at least as far as alerts are concerned). Otherwise, a user might click the submit button when they've entered valid information, and receive an error message in the members page. I just commented out the unset line and ran the code. First I entered wrong information and clicked submit. So $_SESSION now has this in it "you entered an invalid username or password." Then, I entered valid information (so now $_SESSION should also have this in it "You successfully logged in to the members page"). When I did that, I was redirected to the members page. At the top were the alerts. There was an alert saying "You successfully logged in to the members page" and then the error: "you entered an invalid username or password." Just thought others may have been confused like me about why that line of code is in there at all.