In some cases you need to display your post title outside your loop. If you want to display the post title within the loop then its easy you can use <?php echo get_the_title(); ?> or <?php the_title(); ?>
Use following function to display your post title outside loop.
<?php single_post_title( $prefix, $display ); ?>
Where $prefix is text to place before title. and $display is Boolean, if set to TRUE then title is displayed , and set to FALSE then it is returned for use in PHP