Displaying related posts is a very great way to help visitors staying longer on your blog. You can use a plugin, but you also can use tags and a custom code to show related posts. Let’s see how to do!
This code will display related posts based on the current post tag(s). It must be pasted within the loop.
<?php
//for use in the loop, list 5 post titles related to first tag on current post
$tags = wp_get_post_tags($post->ID);
if ($tags) {
  echo ‘Related Posts’;
  $first_tag = $tags[0]->term_id;
  $args=array(
   ‘tag__in’ => array($first_tag),
   ‘post__not_in’ => array($post->ID),
   ‘showposts’=>5,
   ‘caller_get_posts’=>1
  );
  $my_query = new WP_Query($args);
  if( $my_query->have_posts() ) {
   while ($my_query->have_posts()) : $my_query->the_post(); ?>
    <p><a href=”<?php the_permalink() ?>” rel=”bookmark” title=”Permanent Link to <?php the_title_attribute(); ?>”><?php the_title(); ?></a></p>
    <?php
   endwhile;
  }
}
?>