diff --git a/core/modules/comment/comment.entity.inc b/core/modules/comment/comment.entity.inc
index a89d383..62a23d9 100644
--- a/core/modules/comment/comment.entity.inc
+++ b/core/modules/comment/comment.entity.inc
@@ -6,7 +6,7 @@
  */
 
 /**
- * Entity class for comments.
+ * Defines the comment entity class.
  */
 class Comment extends Entity {
 
@@ -49,7 +49,7 @@ class Comment extends Entity {
   /**
    * The comment author's name.
    *
-   * In case of anonymous authors the value as typed in the comment form.
+   * For anonymous authors, this is the value as typed in the comment form.
    *
    * @var string
    */
@@ -58,7 +58,7 @@ class Comment extends Entity {
   /**
    * The comment author's e-mail address.
    *
-   * In case of anonymous authors the value as typed in the comment form.
+   * For anonymous authors, this is the value as typed in the comment form.
    *
    * @var string
    */
@@ -67,7 +67,7 @@ class Comment extends Entity {
   /**
    * The comment author's home page address.
    *
-   * In case of anonymous authors the value as typed in the comment form.
+   * For anonymous authors, this is the value as typed in the comment form.
    *
    * @var string
    */
@@ -76,13 +76,16 @@ class Comment extends Entity {
 }
 
 /**
- * Controller class for comments.
+ * Defines the controller class for comments.
  *
  * This extends the EntityDatabaseStorageController class, adding required
  * special handling for comment entities.
  */
 class CommentStorageController extends EntityDatabaseStorageController {
 
+  /**
+   * Overrides EntityDatabaseStorageController::buildQuery().
+   */
   protected function buildQuery($ids, $conditions = array(), $revision_id = FALSE) {
     $query = parent::buildQuery($ids, $conditions, $revision_id);
     // Specify additional fields from the user and node tables.
@@ -94,6 +97,9 @@ class CommentStorageController extends EntityDatabaseStorageController {
     return $query;
   }
 
+  /**
+   * Overrides EntityDatabaseStorageController::attachLoad().
+   */
   protected function attachLoad(&$comments, $revision_id = FALSE) {
     // Setup standard comment properties.
     foreach ($comments as $key => $comment) {
@@ -106,6 +112,8 @@ class CommentStorageController extends EntityDatabaseStorageController {
   }
 
   /**
+   * Overrides EntityDatabaseStorageController::preSave().
+   *
    * @see comment_int_to_alphadecimal()
    */
   protected function preSave(EntityInterface $comment) {
@@ -179,6 +187,9 @@ class CommentStorageController extends EntityDatabaseStorageController {
     }
   }
 
+  /**
+   * Overrides EntityDatabaseStorageController::postSave().
+   */
   protected function postSave(EntityInterface $comment) {
     // Update the {node_comment_statistics} table prior to executing the hook.
     $this->updateNodeStatistics($comment->nid);
@@ -188,6 +199,9 @@ class CommentStorageController extends EntityDatabaseStorageController {
     }
   }
 
+  /**
+   * Overrides EntityDatabaseStorageController::postDelete().
+   */
   protected function postDelete($comments) {
     // Delete the comments' replies.
     $query = db_select('comment', 'c')
@@ -212,6 +226,9 @@ class CommentStorageController extends EntityDatabaseStorageController {
    *   node or the node authors uid if no comments exists for the node.
    * - comment_count: the total number of approved/published comments on this
    *   node.
+   *
+   * @param $nid
+   *   The node ID.
    */
   protected function updateNodeStatistics($nid) {
     // Allow bulk updates and inserts to temporarily disable the
diff --git a/core/modules/entity/entity.class.inc b/core/modules/entity/entity.class.inc
index 5459b29..2c98143 100644
--- a/core/modules/entity/entity.class.inc
+++ b/core/modules/entity/entity.class.inc
@@ -6,32 +6,36 @@
  */
 
 /**
- * Interface for all entity objects.
+ * Defines a common interface for all entity objects.
  */
 interface EntityInterface {
 
   /**
-   * Creates a new entity object.
+   * Constructs a new entity object.
    *
    * @param $values
-   *   An array of values to set, keyed by property name. If the entity type has
-   *   bundles the bundle key has to be specified.
+   *   An array of values to set, keyed by property name. If the entity type
+   *   has bundles, the bundle key has to be specified.
    * @param $entity_type
    *   The type of the entity to create.
    */
   public function __construct(array $values, $entity_type);
 
   /**
-   * Returns the entity identifier, i.e. the entities machine name or numeric ID.
+   * Returns the entity identifier (the entity's machine name or numeric ID).
    *
    * @return
-   *   The identifier of the entity. In case the entity has no identifier yet,
-   *   it returns NULL.
+   *   The identifier of the entity, or NULL if the entity does not yet have
+   *   an identifier.
    */
   public function id();
 
   /**
-   * Returns whether the entity is new; i.e. whether it has been already saved.
+   * Returns whether the entity is new.
+   *
+   * @return
+   *   TRUE if the entity is new, or FALSE if the entity has already been
+   *   saved.
    */
   public function isNew();
 
@@ -61,12 +65,12 @@ interface EntityInterface {
   public function label();
 
   /**
-   * Returns the uri elements of the entity.
+   * Returns the URI elements of the entity.
    *
    * @return
-   *   An array containing the 'path' and 'options' keys used to build the uri
+   *   An array containing the 'path' and 'options' keys used to build the URI
    *   of the entity, and matching the signature of url(). NULL if the entity
-   *   has no uri of its own.
+   *   has no URI of its own.
    */
   public function uri();
 
@@ -76,14 +80,14 @@ interface EntityInterface {
    * @param $property_name
    *   The name of the property to return; e.g., 'title'.
    * @param $language
-   *   (optional) In case the property is translatable, the language object of
-   *   the language that should be used for getting the property. If set to
-   *   NULL, the default language is being used.
+   *   (optional) If the property is translatable, the language object of the
+   *   language that should be used for getting the property. If set to NULL,
+   *   the default language is being used.
    * @todo
    *   Which default language should be used.
    *
    * @return
-   *   The property value, or NULL in case it is not defined.
+   *   The property value, or NULL if it is not defined.
    */
   public function get($property_name, $language = NULL);
 
@@ -95,8 +99,8 @@ interface EntityInterface {
    * @param $value
    *   The value to set, or NULL to unset the property.
    * @param $language
-   *   (optional) In case the property is translatable, the language object of
-   *   the language that should be used for getting the property. If set to
+   *   (optional) If the property is translatable, the language object of the
+   *   language that should be used for getting the property. If set to
    *   NULL, the default language is being used.
    * @todo
    *   Which default language should be used.
@@ -110,8 +114,7 @@ interface EntityInterface {
    *   In case of failures an exception is thrown.
    *
    * @return
-   *   Either SAVED_NEW or SAVED_UPDATED is returned, depending on the operation
-   *   performed.
+   *   Either SAVED_NEW or SAVED_UPDATED, depending on the operation performed.
    */
   public function save();
 
@@ -145,12 +148,14 @@ interface EntityInterface {
 }
 
 /**
- * Exception thrown when storage operations fail.
+ * Defines an exception thrown when storage operations fail.
  */
 class EntityStorageException extends Exception { }
 
 /**
- * A class implementing the EntityInterface.
+ * Defines a base entity class.
+ *
+ * Default implementation of EntityInterface.
  *
  * This class can be used as-is by simple entity types. Entity types requiring
  * special handling can extend the class.
@@ -165,27 +170,29 @@ class Entity implements EntityInterface {
   protected $entityType;
 
   /**
-   * Info about the entity's type.
+   * Information about the entity's type.
    *
    * @var array
    */
   protected $entityInfo;
 
   /**
-   * The ID entity key.
+   * The entity ID key.
    *
    * @var string
    */
   protected $idKey;
 
   /**
-   * The bundle entity key.
+   * The entity bundle key.
    *
    * @var string
    */
   protected $bundleKey;
 
-
+  /**
+   * Constructs a new entity object.
+   */
   public function __construct(array $values = array(), $entity_type) {
     $this->entityType = $entity_type;
     $this->setUp();
@@ -196,7 +203,7 @@ class Entity implements EntityInterface {
   }
 
   /**
-   * Set up the object instance on construction or unserializiation.
+   * Sets up the object instance on construction or unserializiation.
    */
   protected function setUp() {
     $this->entityInfo = entity_get_info($this->entityType);
@@ -204,26 +211,42 @@ class Entity implements EntityInterface {
     $this->bundleKey = isset($this->entityInfo['entity keys']['bundle']) ? $this->entityInfo['entity keys']['bundle'] : NULL;
   }
 
+  /**
+   * Implements EntityInterface::id().
+   */
   public function id() {
     return isset($this->{$this->idKey}) ? $this->{$this->idKey} : NULL;
   }
 
+  /**
+   * Implements EntityInterface::isNew().
+   */
   public function isNew() {
     // We support creating entities with pre-defined ids to ease migrations.
     // For that the "is_new" property may be set to TRUE.
     return !empty($this->is_new) || empty($this->{$this->idKey});
   }
 
+  /**
+   * Implements EntityInterface::entityType().
+   */
   public function entityType() {
     return $this->entityType;
   }
 
+  /**
+   * Implements EntityInterface::bundle().
+   */
   public function bundle() {
     return isset($this->bundleKey) ? $this->{$this->bundleKey} : $this->entityType;
   }
 
+  /**
+   * Implements EntityInterface::label().
+   *
+   * @see entity_label()
+   */
   public function label() {
-    // @see entity_label()
     $label = FALSE;
     if (isset($this->entityInfo['label callback']) && function_exists($this->entityInfo['label callback'])) {
       $label = $this->entityInfo['label callback']($this->entityType, $this);
@@ -234,8 +257,12 @@ class Entity implements EntityInterface {
     return $label;
   }
 
+  /**
+   * Implements EntityInterface::uri().
+   *
+   * @see entity_uri()
+   */
   public function uri() {
-    // @see entity_uri()
     $bundle = $this->bundle();
     // A bundle-specific callback takes precedence over the generic one for the
     // entity type.
@@ -261,6 +288,8 @@ class Entity implements EntityInterface {
   }
 
   /**
+   * Implements EntityInterface::get().
+   *
    * @todo
    *   Implement default handling of language.
    */
@@ -273,6 +302,8 @@ class Entity implements EntityInterface {
   }
 
   /**
+   * Implements EntityInterface::set().
+   *
    * @todo
    *   Implement default handling of language.
    */
@@ -285,28 +316,42 @@ class Entity implements EntityInterface {
     }
   }
 
+  /**
+   * Implements EntityInterface::save().
+   */
   public function save() {
     return entity_get_controller($this->entityType)->save($this);
   }
 
+  /**
+   * Implements EntityInterface::delete().
+   */
   public function delete() {
     if (!$this->isNew()) {
       entity_get_controller($this->entityType)->delete(array($this->id()));
     }
   }
 
+  /**
+   * Implements EntityInterface::createDuplicate().
+   */
   public function createDuplicate() {
     $duplicate = clone $this;
     $duplicate->{$this->idKey} = NULL;
     return $duplicate;
   }
 
+  /**
+   * Implements EntityInterface::entityInfo().
+   */
   public function entityInfo() {
     return $this->entityInfo;
   }
 
   /**
-   * Magic method to only serialize what is necessary.
+   * Serializes only what is necessary.
+   *
+   * See @link http://www.php.net/manual/en/language.oop5.magic.php#language.oop5.magic.sleep PHP Magic Methods @endlink.
    */
   public function __sleep() {
     $vars = get_object_vars($this);
@@ -317,7 +362,9 @@ class Entity implements EntityInterface {
   }
 
   /**
-   * Magic method to invoke setUp() on unserialization.
+   * Invokes setUp() on unserialization.
+   *
+   * See @link http://www.php.net/manual/en/language.oop5.magic.php#language.oop5.magic.sleep PHP Magic Methods @endlink
    */
   public function __wakeup() {
     $this->setUp();
diff --git a/core/modules/entity/entity.controller.inc b/core/modules/entity/entity.controller.inc
index 29474a6..2498ab4 100644
--- a/core/modules/entity/entity.controller.inc
+++ b/core/modules/entity/entity.controller.inc
@@ -6,7 +6,7 @@
  */
 
 /**
- * Interface for entity controller classes.
+ * Defines a common interface for entity controller classes.
  *
  * All entity controller classes specified via the 'controller class' key
  * returned by hook_entity_info() or hook_entity_info_alter() have to implement
@@ -19,7 +19,7 @@
 interface DrupalEntityControllerInterface {
 
   /**
-   * Constructor.
+   * Constructs a new DrupalEntityControllerInterface object.
    *
    * @param $entityType
    *   The entity type for which the instance is created.
@@ -50,6 +50,8 @@ interface DrupalEntityControllerInterface {
 }
 
 /**
+ * Defines a base entity controller class.
+ *
  * Default implementation of DrupalEntityControllerInterface.
  *
  * This class can be used as-is by most simple entity types. Entity types
@@ -122,7 +124,9 @@ class DrupalDefaultEntityController implements DrupalEntityControllerInterface {
   protected $cache;
 
   /**
-   * Constructor: sets basic variables.
+   * Implements DrupalEntityControllerInterface::__construct().
+   *
+   * Sets basic variables.
    */
   public function __construct($entityType) {
     $this->entityType = $entityType;
@@ -395,7 +399,7 @@ class DrupalDefaultEntityController implements DrupalEntityControllerInterface {
 }
 
 /**
- * Interface for entity storage controllers.
+ * Defines a common interface for entity storage controllers.
  */
 interface EntityStorageControllerInterface extends DrupalEntityControllerInterface {
 
@@ -426,12 +430,12 @@ interface EntityStorageControllerInterface extends DrupalEntityControllerInterfa
 }
 
 /**
- * A controller implementing EntityAPIStorageControllerInterface for the database.
+ * Implements the entity storage controller interface for the database.
  */
 class EntityDatabaseStorageController extends DrupalDefaultEntityController implements EntityStorageControllerInterface {
 
   /**
-   * Implements EntityStorageControllerInterface.
+   * Implements EntityStorageControllerInterface::delete().
    */
   public function delete($ids) {
     $entities = $ids ? $this->load($ids) : FALSE;
@@ -468,7 +472,7 @@ class EntityDatabaseStorageController extends DrupalDefaultEntityController impl
   }
 
   /**
-   * Implements EntityStorageControllerInterface.
+   * Implements EntityStorageControllerInterface::save().
    */
   public function save(EntityInterface $entity) {
     $transaction = db_transaction();
@@ -510,22 +514,31 @@ class EntityDatabaseStorageController extends DrupalDefaultEntityController impl
   }
 
   /**
-   * Act on an entity before the presave hook is invoked.
+   * Acts on an entity before the presave hook is invoked.
+   *
+   * Used before the entity is saved and before invoking the presave hook.
    */
   protected function preSave(EntityInterface $entity) { }
 
   /**
-   * Act on an entity when inserted or updated before the respective hook is invoked.
+   * Acts on a saved entity before the insert or update hook is invoked.
+   *
+   * Used after the entity is saved, but before invoking the insert or update
+   * hook.
    */
   protected function postSave(EntityInterface $entity) { }
 
   /**
-   * Act on entities before they are deleted.
+   * Acts on entities before they are deleted.
+   *
+   * Used before the entities are deleted and before invoking the delete hook.
    */
   protected function preDelete($entities) { }
 
   /**
-   * Act on entities when deleted before the delete hook is invoked.
+   * Acts on deleted entities before the delete hook is invoked.
+   *
+   * Used after the entities are deleted but before invoking the delete hook.
    */
   protected function postDelete($entities) { }
 
diff --git a/core/modules/entity/entity.module b/core/modules/entity/entity.module
index 26efe06..4ac83ff 100644
--- a/core/modules/entity/entity.module
+++ b/core/modules/entity/entity.module
@@ -257,7 +257,7 @@ function entity_load_unchanged($entity_type, $id) {
 }
 
 /**
- * Permanently delete multiple entities.
+ * Deletes multiple entities permanently.
  *
  * @param $entity_type
  *   The type of the entity.
@@ -269,7 +269,7 @@ function entity_delete_multiple($entity_type, $ids) {
 }
 
 /**
- * Construct a new entity object, without saving it to the database.
+ * Constructs a new entity object, without saving it to the database.
  *
  * @param $entity_type
  *   The type of the entity.
diff --git a/core/modules/entity/tests/entity.test b/core/modules/entity/tests/entity.test
index c435541..3733c93 100644
--- a/core/modules/entity/tests/entity.test
+++ b/core/modules/entity/tests/entity.test
@@ -6,7 +6,7 @@
  */
 
 /**
- * Test basic API.
+ * Tests the basic Entity API.
  */
 class EntityAPITestCase extends DrupalWebTestCase {
 
@@ -23,7 +23,7 @@ class EntityAPITestCase extends DrupalWebTestCase {
   }
 
   /**
-   * Tests basic CRUD functionality of the entity API.
+   * Tests basic CRUD functionality of the Entity API.
    */
   function testCRUD() {
     $user1 = $this->drupalCreateUser();
diff --git a/core/modules/entity/tests/entity_test.module b/core/modules/entity/tests/entity_test.module
index 39e2752..4d34232 100644
--- a/core/modules/entity/tests/entity_test.module
+++ b/core/modules/entity/tests/entity_test.module
@@ -25,7 +25,7 @@ function entity_test_entity_info() {
 }
 
 /**
- * Load a test-entity.
+ * Loads a test-entity.
  *
  * @param $id
  *   A test-entity ID.