Me puede explicar este código
<!-- DOCTYPE html -->
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:p="http://primefaces.org/ui"
xmlns:f="http://java.sun.com/jsf/core">
<!---->
<f:view contentType="text/html" id="fview">
<!--
<meta http-equiv="Content-Type" content="text/html;" charset="utf-8" />
-->
<!---->
<!--TITULO-->
<title>MCDWEB</title>
<!--ICONO-->
<link rel="shortcut icon" href="${request.contextPath}/images/favicon.ico" />
<ui:debug />
<f:metadata>
<ui:insert name="metadata" />
</f:metadata>
<!--estilo-->
<h:head>
<link href="#{request.contextPath}/resources/styles/default.css" type="text/css" rel="stylesheet" />
</h:head>
<!--No mostrar cargado-->
<h:body onload="statusDialog.hide();">
<p:ajaxStatus onstart="statusDialog.show();" onsuccess="statusDialog.hide();" />
<!--divisor-->
<div style="width:100%;">
<div>
<!--imagen de gobierno-->
<h:graphicImage value="#{request.contextPath}/../resources/images/cintillo_1024x768.png" style="width: 100%;"/>
</div>
<!--divisor segudario-->
<div class="row" style="margin-top:0px;">
<!--imagen cantv-->
<div style="float:left;">
<h:graphicImage value="#{request.contextPath}/../resources/images/logoCantv_portal.jpg" />
</div>
<!--logo del titulo de gestor....-->
<div id="title" style="width:100%; float:center;">
<h:outputText value="#{msg['header']}" styleClass="headerTitle"/>
</div>
</div>
</div>
<!--style de usuario-->
<p:layout id="layout" resizable="false" style="height:400px;" >
<p:layoutUnit position="center" resizable="false" style="border: 0px">
<div id="content-page" class="content-page labelData">
<p:growl id="msgsGrowl" autoUpdate="true" showDetail="true" closable="true" escape="false"/>
<h:panelGrid rendered="#{param.login_error == 1 and SPRING_SECURITY_LAST_EXCEPTION != null}">
<span class="msg-error">#{SPRING_SECURITY_LAST_EXCEPTION.message}</span>
</h:panelGrid>
<h:form id="login" prependId="false" onsubmit="document.#{p:component('login')}.action='#{request.contextPath}/j_spring_security_check';"
method="post">
<p:growl id="growl" showDetail="true" sticky="false" />
<p:panel header="#{msg['login']}" styleClass="hlogin labelForm">
<h:panelGrid columns="2" cellpadding="5">
<h:outputText value="#{msg['login.username']}:" />
<p:inputText id="j_username" name="j_username" required="true"/>
<h:outputText value="#{msg['login.password']}:" />
<p:password id="j_password" name="j_password" required="true" />
</h:panelGrid>
<div style="text-align:center;">
<p:commandButton value="#{msg['button.login']}" ajax="false"/>
</div>
</p:panel>
</h:form>
</div>
</p:layoutUnit>
</p:layout>
<div id="south-page" style="width:100%; height:100%; text-align: center" >
<ui:include src="templates/footer.xhtml" />
</div>
<p:dialog modal="true" widgetVar="statusDialog" showHeader="false"
draggable="false" closable="false" resizable="false"
visible="false" position="center" maximizable="false" minimizable="false" style="font-size:500px;">
<h:graphicImage value="#{request.contextPath}/../resources/images/ajax-loader.gif" />
</p:dialog>
</h:body>
</f:view>
</html>
