Updating custom module I created custom module and I installed it on "Add Module" page. I've got that module in sites/all/modules. I changed that module (I went to that location and I recoded it). What should I do to update that module. It seems to me that only after recoding that module Drupal doesn't notice changes.
When you edit an installed and enabled module, Drupal will not notice you added new hooks, since the list of the hooks implemented by a module is cached from Drupal. In order to make Drupal notice you edited the module and added new hooks, you need to disable and re-enable the module, without uninstalling it.

The reason why this is necessary is that module_implements(), the function that returns TRUE when a module implements a hook, contains the following code.

  // Fetch implementations from cache.
  if (empty($implementations)) {
    $implementations = cache_get('module_implements', 'cache_bootstrap');
    if ($implementations === FALSE) {
      $implementations = array();
    }
    else {
      $implementations = $implementations-&gt;data;
    }
  }