diff --git a/fivestar.migrate.inc b/fivestar.migrate.inc
index 77a6d90..9e468b4 100644
--- a/fivestar.migrate.inc
+++ b/fivestar.migrate.inc
@@ -22,14 +22,14 @@ function fivestar_migrate_api() {
 class MigrateFivestarFieldHandler extends MigrateFieldHandler {
 
   /**
-   * Constructor function.
+   * Constructor, initialize registerTypes.
    */
   public function __construct() {
     $this->registerTypes(array('fivestar'));
   }
 
   /**
-   * Function fields() implementation.
+   * {@inheritdoc}
    */
   public function fields($type, $parent_field, $migration = NULL) {
     $fields = array(
@@ -54,7 +54,7 @@ class MigrateFivestarFieldHandler extends MigrateFieldHandler {
       $return[$language][$delta] = array('rating' => $value) + array_intersect_key($arguments, $field_info['columns']);
     }
 
-    return isset($return) ? $return : NULL;
+    return $return ?? NULL;
   }
 
 }
diff --git a/fivestar.module b/fivestar.module
index 83a9316..aa49890 100644
--- a/fivestar.module
+++ b/fivestar.module
@@ -201,13 +201,12 @@ function _fivestar_variables() {
 }
 
 /**
- * Internal function to handle vote casting, flood control, XSS, IP based
- * voting, etc...
+ * Internal function to handle vote casting, flood control, XSS, IP based etc..
  */
 function _fivestar_cast_vote($entity_type, $id, $value, $tag = NULL, $uid = NULL, $skip_validation = FALSE, $vote_source = NULL) {
   global $user;
   $tag = empty($tag) ? 'vote' : $tag;
-  $uid = isset($uid) ? $uid : $user->uid;
+  $uid = $uid ?? $user->uid;
   // Bail out if the user's trying to vote on an invalid object.
   if (!$skip_validation && !fivestar_validate_target($entity_type, $id, $tag, $uid)) {
     return array();
@@ -260,14 +259,14 @@ function _fivestar_cast_vote($entity_type, $id, $value, $tag = NULL, $uid = NULL
  *
  * @param string $entity_type
  *   The Entity type for which to retrieve votes.
- * @param int $id
+ * @param int $ids
  *   The ID for which to retrieve votes.
  * @param string $tag
  *   The VotingAPI tag for which to retrieve votes.
  * @param int $uid
  *   Optional. A user ID for which to retrieve votes.
  *
- * @return
+ * @return array
  *   An array of the following keys:
  *   - average: An array of VotingAPI results, including the average 'value'.
  *   - count: An array of VotingAPI results, including the count 'value'.
@@ -332,6 +331,20 @@ function fivestar_get_votes_multiple($entity_type, $ids, $tag = 'vote', $uid = N
 
 /**
  * Implementing function fivestar_get_votes().
+ *
+ * @param string $entity_type
+ *   The Entity type for which to retrieve votes.
+ * @param int $id
+ *   The ID for which to retrieve votes.
+ * @param string $tag
+ *   The VotingAPI tag for which to retrieve votes.
+ * @param int $uid
+ *   Optional. A user ID for which to retrieve votes.
+ *
+ * @return array
+ *   An array of the following keys:
+ *   - entity_type: An array of VotingAPI results, including the entity_type.
+ *   - id: An array of VotingAPI results, including the id.
  */
 function fivestar_get_votes($entity_type, $id, $tag = 'vote', $uid = NULL) {
   $multiple = fivestar_get_votes_multiple($entity_type, array($id), $tag, $uid);
@@ -351,6 +364,8 @@ function fivestar_get_votes($entity_type, $id, $tag = 'vote', $uid = NULL) {
  *   The user trying to cast the vote.
  *
  * @return bool
+ *   Returns TRUE if vote is a valid.
+ *   Returns FALSE if vote is invalid.
  */
 function fivestar_validate_target($entity_type, $id, $tag, $uid = NULL) {
   if (!isset($uid)) {
@@ -497,7 +512,7 @@ function fivestar_fivestar_widgets() {
  *   - tag: The VotingAPI tag that will be registered by this widget. Defaults
  *     to "vote".
  */
-function fivestar_custom_widget($form, &$form_state, $values, $settings) {
+function fivestar_custom_widget($form, array $form_state, array $values, array $settings) {
   $form = array(
     '#attributes' => array(
       'class' => array('fivestar-widget'),
@@ -579,9 +594,9 @@ function fivestar_ajax_submit($form, $form_state) {
   }
 
   $values = array();
-  $values['user'] = isset($votes['user']['value']) ? $votes['user']['value'] : 0;
-  $values['average'] = isset($votes['average']['value']) ? $votes['average']['value'] : 0;
-  $values['count'] = isset($votes['count']['value']) ? $votes['count']['value'] : 0;
+  $values['user'] = $votes['user']['value'] ?? 0;
+  $values['average'] = $votes['average']['value'] ?? 0;
+  $values['count'] = $votes['count']['value'] ?? 0;
 
   // We need to process the 'fivestar' element with the new values.
   $form['vote']['#values'] = $values;
@@ -590,7 +605,7 @@ function fivestar_ajax_submit($form, $form_state) {
   $new_element = fivestar_expand($form['vote'], $form_state, $form_state['complete form']);
   // Update the description. Since it doesn't account of our cast vote above.
   // @todo Look into all this, I honestly don't like it and it's a bit weird.
-  $form['vote']['vote']['#description'] = isset($new_element['vote']['#description']) ? $new_element['vote']['#description'] : '';
+  $form['vote']['vote']['#description'] = $new_element['vote']['#description'] ?? '';
   if (!$form['vote']['#allow_revote'] && !$form['vote']['#allow_clear']) {
     $form['vote'] = $new_element;
   }
@@ -765,8 +780,8 @@ function fivestar_expand($element, $form_state, $complete_form) {
       ));
       if ($settings['text'] != 'none') {
         $static_description = theme('fivestar_summary', array(
-          'average_rating' => $settings['text'] == 'user' ? NULL : (isset($values['average']) ? $values['average'] : 0),
-          'votes' => isset($values['count']) ? $values['count'] : 0,
+          'average_rating' => $settings['text'] == 'user' ? NULL : ($values['average'] ?? 0),
+          'votes' => $values['count'] ?? 0,
           'stars' => $settings['stars'],
         ));
       }
@@ -830,10 +845,10 @@ function fivestar_expand($element, $form_state, $complete_form) {
  * @param array $element
  *   The fivestar element.
  *
- * @return
+ * @return default_value
  *   The default value for the element.
  */
-function _fivestar_get_element_default_value($element) {
+function _fivestar_get_element_default_value(array $element) {
   if (isset($element['#default_value'])) {
     $default_value = $element['#default_value'];
   }
@@ -889,7 +904,7 @@ function fivestar_votingapi_metadata_alter(&$data) {
   foreach (fivestar_get_tags() as $tag) {
     // Add several custom tags that are being used by fivestar.
     $data['tags'][$tag] = array(
-      'name' => t($tag),
+      'name' => $tag,
       'description' => t('@tag used by fivestar.', array('@tag' => $tag)),
       'module' => 'fivestar',
     );
@@ -1023,6 +1038,7 @@ function fivestar_fivestar_target_info($field, $instance) {
 }
 
 /**
+ * Implementing function _fivestar_target_node_reference().
  *
  * @return array
  *   array('entity_type', 'entity_id').
@@ -1040,7 +1056,10 @@ function _fivestar_target_node_reference($entity, $field, $instance, $langcode)
 }
 
 /**
- * @return (array) array('entity_type', 'entity_id')
+ * Implementing function _fivestar_target_entityreference().
+ *
+ * @return array
+ *   array('entity_type', 'entity_id').
  */
 function _fivestar_target_entityreference($entity, $field, $instance, $langcode) {
   $target = array();
@@ -1059,6 +1078,7 @@ function _fivestar_target_entityreference($entity, $field, $instance, $langcode)
 }
 
 /**
+ * Implementing function _fivestar_target_user_reference().
  *
  * @return array
  *   array('entity_type', 'entity_id').
@@ -1089,6 +1109,8 @@ function _fivestar_target_comment_parent_node($entity, $field, $instance, $langc
  * Helper function to determine if a user can vote on content.
  *
  * @return bool
+ *   Returns TRUE if a user can vote.
+ *   Returns FALSE if a user cannot vote.
  */
 function _fivestar_allow_vote($element) {
   global $user;
@@ -1100,9 +1122,9 @@ function _fivestar_allow_vote($element) {
   }
   else {
     $criteria = array(
-      'entity_id' => isset($element['#settings']['content_id']) ? $element['#settings']['content_id'] : NULL,
-      'entity_type' => isset($element['#settings']['content_type']) ? $element['#settings']['content_type'] : NULL,
-      'tag' => isset($element['#settings']['tag']) ? $element['#settings']['tag'] : NULL,
+      'entity_id' => $element['#settings']['content_id'] ?? NULL,
+      'entity_type' => $element['#settings']['content_type'] ?? NULL,
+      'tag' => $element['#settings']['tag'] ?? NULL,
       'uid' => $user->uid,
     );
 
@@ -1128,11 +1150,11 @@ function _fivestar_allow_vote($element) {
 }
 
 /**
- * Implements hook_ctools_content_subtype_alter()
+ * Implements hook_alter().
  */
 function fivestar_ctools_content_subtype_alter(&$subtype, &$plugin) {
   if ($plugin['name'] == 'entity_field' && isset($subtype['subtype_id'])) {
-    list($entity_type, $field_name) = explode(':', $subtype['subtype_id'], 2);
+    [$entity_type, $field_name] = explode(':', $subtype['subtype_id'], 2);
     $field = field_info_field($field_name);
     if ($field['type'] == 'fivestar') {
       $subtype['render callback'] = 'fivestar_fivestar_field_content_type_render';
@@ -1150,7 +1172,7 @@ function fivestar_fivestar_field_content_type_render($subtype, $conf, $panel_arg
 
   // Get a shortcut to the entity.
   $entity = $context->data;
-  list($entity_type, $field_name) = explode(':', $subtype, 2);
+  [$entity_type, $field_name] = explode(':', $subtype, 2);
 
   // Load the entity type's information for this field.
   $ids = entity_extract_ids($entity_type, $entity);
diff --git a/includes/fivestar.field.inc b/includes/fivestar.field.inc
index 0407aab..3d1b045 100644
--- a/includes/fivestar.field.inc
+++ b/includes/fivestar.field.inc
@@ -55,7 +55,7 @@ function fivestar_field_settings_form($field, $instance) {
     '#title' => 'Voting Tag',
     '#options' => fivestar_get_tags(),
     '#description' => t('The tag this rating will affect. Enter a property on which that this rating will affect, such as <em>quality</em>, <em>satisfaction</em>, <em>overall</em>, etc.'),
-    '#default_value' => isset($field['settings']['axis']) ? $field['settings']['axis'] : '',
+    '#default_value' => $field['settings']['axis'] ?? '',
     '#disabled' => field_has_data($field),
   );
 
@@ -73,27 +73,27 @@ function fivestar_field_instance_settings_form($field, $instance) {
     '#type' => 'select',
     '#title' => check_plain($widget_title),
     '#options' => drupal_map_assoc(range(1, 10)),
-    '#default_value' => isset($instance['settings']['stars']) ? $instance['settings']['stars'] : 5,
+    '#default_value' => $instance['settings']['stars'] ?? 5,
   );
 
   $form['allow_clear'] = array(
     '#type' => 'checkbox',
     '#title' => t('Allow users to cancel their ratings.'),
-    '#default_value' => isset($instance['settings']['allow_clear']) ? $instance['settings']['allow_clear'] : FALSE,
+    '#default_value' => $instance['settings']['allow_clear'] ?? FALSE,
     '#return_value' => 1,
   );
 
   $form['allow_revote'] = array(
     '#type' => 'checkbox',
     '#title' => t('Allow users to re-vote on already voted content.'),
-    '#default_value' => isset($instance['settings']['allow_revote']) ? $instance['settings']['allow_revote'] : TRUE,
+    '#default_value' => $instance['settings']['allow_revote'] ?? TRUE,
     '#return_value' => 1,
   );
 
   $form['allow_ownvote'] = array(
     '#type' => 'checkbox',
     '#title' => t('Allow users to vote on their own content.'),
-    '#default_value' => isset($instance['settings']['allow_ownvote']) ? $instance['settings']['allow_ownvote'] : TRUE,
+    '#default_value' => $instance['settings']['allow_ownvote'] ?? TRUE,
     '#return_value' => 1,
   );
 
@@ -194,7 +194,7 @@ function _fivestar_field_target($entity, $field, $instance, $item, $langcode) {
   else {
     // If all else fails, default to voting on the
     // instance the field is attached to.
-    list($id, $vid, $bundle) = entity_extract_ids($instance['entity_type'], $entity);
+    [$id, $vid, $bundle] = entity_extract_ids($instance['entity_type'], $entity);
     $target = array(
       'entity_id' => $id,
       'entity_type' => $instance['entity_type'],
@@ -208,7 +208,7 @@ function _fivestar_field_target($entity, $field, $instance, $item, $langcode) {
  */
 function _fivestar_update_field_value($entity_type, $entity, $field_name, $langcode, $value) {
   $entity->{$field_name}[$langcode][0]['rating'] = $value;
-  $entity->original = isset($entity->original) ? $entity->original : NULL;
+  $entity->original = $entity->original ?? NULL;
   field_attach_presave($entity_type, $entity);
   field_attach_update($entity_type, $entity);
 }
@@ -269,7 +269,7 @@ function fivestar_field_widget_settings_form($field, $instance) {
     $form['widget']['fivestar_widget'] = array(
       '#type' => 'radios',
       '#options' => array('default' => t('Default')) + $widgets,
-      '#default_value' => isset($instance['widget']['settings']['widget']['fivestar_widget']) ? $instance['widget']['settings']['widget']['fivestar_widget'] : 'default',
+      '#default_value' => $instance['widget']['settings']['widget']['fivestar_widget'] ?? 'default',
       '#attributes' => array('class' => array('fivestar-widgets', 'clearfix')),
       '#pre_render' => array('fivestar_previews_expand'),
       '#attached' => array('css' => array(drupal_get_path('module', 'fivestar') . '/css/fivestar-admin.css')),
@@ -314,15 +314,15 @@ function fivestar_field_widget_form(&$form, &$form_state, $field, $instance, $la
       '#type' => 'select',
       '#title' => check_plain(isset($instance['label']) ? (($i18n) ? i18n_field_translate_property($instance, 'label') : t($instance['label'])) : FALSE),
       '#options' => $options,
-      '#default_value' => isset($items[$delta]['rating']) ? $items[$delta]['rating'] : NULL,
+      '#default_value' => $items[$delta]['rating'] ?? NULL,
       '#description' => check_plain(isset($instance['description']) ? (($i18n) ? i18n_field_translate_property($instance, 'description') : t($instance['description'])) : FALSE),
-      '#required' => isset($instance['required']) ? $instance['required'] : FALSE,
+      '#required' => $instance['required'] ?? FALSE,
     );
   }
 
   elseif ($instance['widget']['type'] == 'stars') {
     $widgets = module_invoke_all('fivestar_widgets');
-    $active = isset($instance['widget']['settings']['widget']['fivestar_widget']) ? $instance['widget']['settings']['widget']['fivestar_widget'] : 'default';
+    $active = $instance['widget']['settings']['widget']['fivestar_widget'] ?? 'default';
     $widget = array(
       'name' => isset($widgets[$active]) ? strtolower($widgets[$active]) : 'default',
       'css' => $active,
@@ -347,16 +347,16 @@ function fivestar_field_widget_form(&$form, &$form_state, $field, $instance, $la
     $element['rating'] = array(
       '#type' => 'fivestar',
       '#title' => check_plain(isset($instance['label']) ? (($i18n) ? i18n_field_translate_property($instance, 'label') : t($instance['label'])) : FALSE),
-      '#stars' => isset($instance['settings']['stars']) ? $instance['settings']['stars'] : 5,
-      '#allow_clear' => isset($instance['settings']['allow_clear']) ? $instance['settings']['allow_clear'] : FALSE,
-      '#allow_revote' => isset($instance['settings']['allow_revote']) ? $instance['settings']['allow_revote'] : FALSE,
-      '#allow_ownvote' => isset($instance['settings']['allow_ownvote']) ? $instance['settings']['allow_ownvote'] : FALSE,
-      '#default_value' => isset($items[$delta]['rating']) ? $items[$delta]['rating'] : (isset($instance['default_value'][$delta]['rating']) ? $instance['default_value'][$delta]['rating'] : 0),
+      '#stars' => $instance['settings']['stars'] ?? 5,
+      '#allow_clear' => $instance['settings']['allow_clear'] ?? FALSE,
+      '#allow_revote' => $instance['settings']['allow_revote'] ?? FALSE,
+      '#allow_ownvote' => $instance['settings']['allow_ownvote'] ?? FALSE,
+      '#default_value' => $items[$delta]['rating'] ?? ($instance['default_value'][$delta]['rating'] ?? 0),
       '#widget' => $widget,
       '#settings' => $settings,
       '#values' => $values,
       '#description' => check_plain(isset($instance['description']) ? (($i18n) ? i18n_field_translate_property($instance, 'description') : t($instance['description'])) : FALSE),
-      '#required' => isset($instance['required']) ? $instance['required'] : FALSE,
+      '#required' => $instance['required'] ?? FALSE,
     );
   }
 
@@ -420,7 +420,7 @@ function fivestar_field_formatter_settings_form($field, $instance, $view_mode, $
   $element['widget']['fivestar_widget'] = array(
     '#type' => 'radios',
     '#options' => array('default' => t('Default')) + $widgets,
-    '#default_value' => isset($settings['widget']['fivestar_widget']) ? $settings['widget']['fivestar_widget'] : 'default',
+    '#default_value' => $settings['widget']['fivestar_widget'] ?? 'default',
     '#attributes' => array('class' => array('fivestar-widgets', 'clearfix')),
     '#pre_render' => array('fivestar_previews_expand'),
     '#attached' => array('css' => array(drupal_get_path('module', 'fivestar') . '/css/fivestar-admin.css')),
@@ -486,7 +486,7 @@ function fivestar_field_formatter_settings_summary($field, $instance, $view_mode
   }
 
   $summary = t("Style: @widget, Stars display: @style, Text display: @text", array(
-    '@widget' => isset($widgets[$settings['widget']['fivestar_widget']]) ? $widgets[$settings['widget']['fivestar_widget']] : t('default'),
+    '@widget' => $widgets[$settings['widget']['fivestar_widget']] ?? t('default'),
     '@style' => strtolower($settings['style']),
     '@text' => strtolower($settings['text']),
   ));
@@ -533,7 +533,7 @@ function fivestar_field_formatter_view($entity_type, $entity, $field, $instance,
     // @todo Get rid of voting categories setting, then change this so
     // axis = field name.
     $tag = (isset($field['settings']['axis'])) ? $field['settings']['axis'] : 'vote';
-    list($id, $vid, $bundle) = entity_extract_ids($entity_type, $entity);
+    [$id, $vid, $bundle] = entity_extract_ids($entity_type, $entity);
     $settings = _fivestar_custom_widget_settings($entity_type, $instance, $display, $id, $tag, $widget);
     // Store entity and field data for later reuse.
     $settings += array(
@@ -776,9 +776,9 @@ function fivestar_field_prepare_view($entity_type, $entities, $field, $instances
       foreach ($votes[$entity_type] as $id => $vote) {
         // Populating the $items[$id] array even for items with no value forces
         // the render system to output a widget.
-        $values['user'] = isset($vote['user']['value']) ? $vote['user']['value'] : 0;
-        $values['average'] = isset($vote['average']['value']) ? $vote['average']['value'] : 0;
-        $values['count'] = isset($vote['count']['value']) ? $vote['count']['value'] : 0;
+        $values['user'] = $vote['user']['value'] ?? 0;
+        $values['average'] = $vote['average']['value'] ?? 0;
+        $values['count'] = $vote['count']['value'] ?? 0;
         $items[$id] = array($values);
       }
     }
@@ -828,7 +828,7 @@ function _fivestar_field_property_values($entity, array $options, $name, $entity
   $values = array();
   if (isset($entity->{$name}[$langcode])) {
     foreach ($entity->{$name}[$langcode] as $delta => $data) {
-      $values[$delta]['user_rating'] = isset($data['rating']) ? $data['rating'] : NULL;
+      $values[$delta]['user_rating'] = $data['rating'] ?? NULL;
       $result = array();
       $result = votingapi_select_results(array(
         'entity_type' => $entity_type,
@@ -837,7 +837,7 @@ function _fivestar_field_property_values($entity, array $options, $name, $entity
         'tag' => $field['settings']['axis'],
         'function' => 'average',
       ));
-      $values[$delta]['average_rating'] = (isset($result[0]['value']) ? $result[0]['value'] : 0);
+      $values[$delta]['average_rating'] = ($result[0]['value'] ?? 0);
     }
   }
   // For an empty single-valued field, we have to return NULL.
diff --git a/includes/fivestar.theme.inc b/includes/fivestar.theme.inc
index 2983647..9c083db 100644
--- a/includes/fivestar.theme.inc
+++ b/includes/fivestar.theme.inc
@@ -33,7 +33,7 @@ function theme_fivestar_preview_widget($variables) {
     '#allow_revote' => TRUE,
     '#allow_ownvote' => TRUE,
     '#widget' => array(
-      'name' => isset($variables['name']) ? $variables['name'] : 'default',
+      'name' => $variables['name'] ?? 'default',
       'css' => isset($variables['css']) && $variables['css'] != 'default' ? $variables['css'] : FALSE,
     ),
   );