[Drupal] How to add the js file and js code block in Drupal

Drupal 6:

 

  // This will add a JS file to your head (specifically the $scripts variable in page.tpl.php)
  drupal_add_js(drupal_get_path('module', 'my_module') . '/my_module.js');

  // This add inline JS to the head of the document
  drupal_add_js('alert("Hello!")', 'inline');

  // This will add variables in the Drupal.settings object
  drupal_add_js(array('my_module' => array('my_setting' => 'this_value')), 'setting');
  
  //add an external JS file to your site.
  //You can not add <script XXXX  />, but you have to add as <script XXX></script>,
  //because the first one will cause some problem (webkit-base browser)
  drupal_set_html_head('<script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=false"></script>');

 Drupal 7:

  drupal_add_js('misc/collapse.js');
  drupal_add_js('misc/collapse.js', 'file');
  drupal_add_js('jQuery(document).ready(function () { alert("Hello!"); });', 'inline');
  drupal_add_js('jQuery(document).ready(function () { alert("Hello!"); });',
    array('type' => 'inline', 'scope' => 'footer', 'weight' => 5)
  );
  drupal_add_js('http://example.com/example.js', 'external');
  drupal_add_js(array('myModule' => array('key' => 'value')), 'setting');

Details: http://api.drupal.org/api/drupal/includes--common.inc/function/drupal_add_js