Calling category ID from The Loop

I’m trying to determine how to directly reference a category in my loop. I created a new template page based off of the Blog template. This will be to display only posts from the category “latest-news.”

I think I found out how to do it, but the code appears to be from earlier versions of wordpress.

Here’s what I tried.

<?php query_posts('category_name=world-dryer-events'); ?>
        <?php if ( have_posts() ) :
            while ( have_posts() ) : the_post();
                $paged = get_query_var( 'paged' ) ? get_query_var( 'paged' ) : 1;
                    $args = array('
                        offset'=> 0,
                        'paged'=>$paged,
                        'posts_per_page' => get_option('posts_per_page'),
                        'post_type' => 'post'
                        );
                    $all_posts = new WP_Query($args);
                    while($all_posts->have_posts()) : $all_posts->the_post(); ?>

                    <?php
                    /* Include the Post-Format-specific template for the content.
                     * If you want to overload this in a child theme then include a file
                     * called content-___.php (where ___ is the Post Format name) and that will be used instead.
                     */
                    $format = get_post_format();
                    if( false === $format )  $format = 'standard';
                    get_template_part( 'postformats/'.$format, 'medium' );

                    ?>

                    <?php endwhile;
            endwhile; ?>

The part I’m mainly concerned about is the first bit where I attempt to filter the posts down to posts from category “latest-news”:

<?php query_posts('category_name=world-dryer-events'); ?>

I’ve also seen it done like these:

‘category=world-dryer-events’

‘cat=6’

Anybody know how to make that first line filter only posts from the category I mentioned?

Thanks.