wordpress login form. place anywhere in your theme templates to display the form

wp-login.php

<?php 
//show the form if the user is not logged in
if( !is_user_logged_in() ): 
     wp_login_form(); 
else: 
     $redirect = home_url();
     echo '<a href="'.wp_logout_url( $redirect ).'">Log Out</a>';
endif;
?>