How do I completely disable cache?

Question

Drupal 6's cache can be set to disabled, normal or aggressive. I cannot find these options for my Drupal 7 installation. There is only a button that flushes all the cache but it has to be clicked for every change I made to a module or a template. By change I mean adding some HTML tags to a module or a template.

Thanks to mirzu's response, I already installed the devel module but it doesn't work either. The only way I get so see my changes is by disabling and enabling the module.

The hello.module looks like:

function annotate_menu() {
  $items = array();
  $items['hello'] = array(
    'title'            => t('Hello world'),
    'page callback'    => 'hello_output',
    'access arguments' => array('access content'),
  );

  return $items;
}

function hello_output() {
  header('Content-type: text/plain; charset=UTF-8');
  header('Content-Disposition: inline');
  return 'annotate';
}

The template page-hello.tpl.php contains print $content;.

I access the page through http://localhost/test/hello.

Answer 1

Completely disable the cache and use the devel module and check the box that reads "rebuild the cache registry on each page load."