Customizing the Loop with WP_Query

WP-Query.php

<?php // The WordPress Loop - customized with WP_Query
$custom_query = new WP_Query('cat=-9'); // exclude Asides category
while($custom_query->have_posts()) : $custom_query->the_post();
...
endwhile;
wp_reset_postdata(); // reset the query
?>

// more examples
<?php 
  $custom_query = new WP_Query('cat=-7,-8,-9'); // exclude any categories
  $custom_query = new WP_Query('posts_per_page=3'); // limit number of posts
  $custom_query = new WP_Query('order=ASC'); // reverse the post order
  $custom_query = new WP_Query('cat=-7,-8,-9&posts_per_page=3&order=ASC');