diff --git a/block_mytreestudyplan.php b/block_mytreestudyplan.php
index 4a3e43f..b958e26 100644
--- a/block_mytreestudyplan.php
+++ b/block_mytreestudyplan.php
@@ -14,6 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <https://www.gnu.org/licenses/>.
 /**
+ * Main block code
  *
  * @package    block_mytreestudyplan
  * @copyright  2023 P.M. Kuipers
@@ -22,13 +23,20 @@
 
 use local_treestudyplan\studyplan;
 
+/**
+ * MyTreestudyplan block base code
+ */
 class block_mytreestudyplan extends \block_base {
 
-    public $levelset;
-
+    /**
+     * Plugin initialization (before $this->config and $this->page are loaded)
+     */
     public function init() {
     }
 
+    /**
+     * Plugin specialization (directly called after $this->config and $this->page are ready)
+     */
     public function specialization() {
         global $CFG;
         $this->title = get_string('title', 'block_mytreestudyplan');
@@ -51,6 +59,9 @@ class block_mytreestudyplan extends \block_base {
         }
     }
 
+    /**
+     * Publish the pages this block can be shown on
+     */
     public function applicable_formats() {
         // Limit this block to the site index and the dashboard (my) pages.
         return [
@@ -62,6 +73,9 @@ class block_mytreestudyplan extends \block_base {
         ];
     }
 
+    /**
+     * Render block content
+     */
     public function get_content() {
         global $CFG;
         global $USER;
@@ -98,10 +112,16 @@ class block_mytreestudyplan extends \block_base {
         return $this->content;
     }
 
+    /**
+     * Whether to hide the header or not
+     */
     public function hide_header() {
         return false;
     }
 
+    /**
+     * Whether this block has config or not
+     */
     public function has_config() {
         return false;
     }
diff --git a/build.php b/build.php
index e83604c..4d033ac 100644
--- a/build.php
+++ b/build.php
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <https://www.gnu.org/licenses/>.
 /**
- *
+ * Build script to properly create a distribution zip
  * @package    block_mytreestudyplan
  * @copyright  2023 P.M. Kuipers
  * @license    https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
diff --git a/db/access.php b/db/access.php
index 7bc4266..2cd8c8a 100644
--- a/db/access.php
+++ b/db/access.php
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <https://www.gnu.org/licenses/>.
 /**
- *
+ * Permission descriptions
  * @package    block_mytreestudyplan
  * @copyright  2023 P.M. Kuipers
  * @license    https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
diff --git a/lang/en/block_mytreestudyplan.php b/lang/en/block_mytreestudyplan.php
index f16d122..c69828a 100644
--- a/lang/en/block_mytreestudyplan.php
+++ b/lang/en/block_mytreestudyplan.php
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <https://www.gnu.org/licenses/>.
 /**
- *
+ * English language file
  * @package    block_mytreestudyplan
  * @copyright  2023 P.M. Kuipers
  * @license    https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
diff --git a/lang/nl/block_mytreestudyplan.php b/lang/nl/block_mytreestudyplan.php
index 83bf69a..4328e7c 100644
--- a/lang/nl/block_mytreestudyplan.php
+++ b/lang/nl/block_mytreestudyplan.php
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <https://www.gnu.org/licenses/>.
 /**
- *
+ * Dutch language file
  * @package    block_mytreestudyplan
  * @copyright  2023 P.M. Kuipers
  * @license    https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
diff --git a/lib.php b/lib.php
index 7a8c719..b35e30c 100644
--- a/lib.php
+++ b/lib.php
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <https://www.gnu.org/licenses/>.
 /**
- *
+ * Library page
  * @package    block_mytreestudyplan
  * @copyright  2023 P.M. Kuipers
  * @license    https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
diff --git a/settings.php b/settings.php
index 7a8c719..e4823a1 100644
--- a/settings.php
+++ b/settings.php
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <https://www.gnu.org/licenses/>.
 /**
- *
+ * Settings page
  * @package    block_mytreestudyplan
  * @copyright  2023 P.M. Kuipers
  * @license    https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
diff --git a/version.php b/version.php
index bbf0ca1..fb614cd 100644
--- a/version.php
+++ b/version.php
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <https://www.gnu.org/licenses/>.
 /**
- *
+ * Version description
  * @package    block_mytreestudyplan
  * @copyright  2023 P.M. Kuipers
  * @license    https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later