Drupal 8 - Get Nodes, Many Ways (load, route, php, from db)

Drupal 8 - Get Nodes, Many Ways (load, route, php, from db)

// Load a node
$listing_page_node = \Drupal\node\Entity\Node::load($node_id);

// Get current node from the route
\Drupal::routeMatch()->getParameter('node')
\Drupal::routeMatch()->getParameter('node')->getType()

// Get node in PHP and get field
if(\Drupal::routeMatch()->getParameters()->has('node')) {
    $current_node = \Drupal::routeMatch()->getParameter('node');
    if($current_node->getType() === 'campaign_page') {
        $variables['show_limited_menu'] = $current_node->get('field_show_limited_menu')->value;
    }
}

// Get nodes from database, sort, filter and prepare display mode render array
$query = \Drupal::entityQuery('node')
                ->condition('type', 'product_service_detail')
                ->condition('status', 1)
                ->sort('created', 'DESC')
                ->range(0, 4);
                $nids = $query->execute();
                $nodes = entity_load_multiple('node', $nids);
                $variables['featured_nodes'] = \Drupal::entityTypeManager()->getViewBuilder('node')->viewMultiple($nodes, 'card');