Menu items shown in Navigation menu?
It's because you're using the MENU_NORMAL_ITEM type, which will add the item to a menu, and haven't set a menu_name. From the docs:


  "menu_name": Optional. Set this to a custom menu if you don't want your item to be placed in Navigation.


If you want to add the link to a different menu try something like this:

$items['test1'] = array(
  'title callback'   =&gt; 'test_callback1',
  'page callback'    =&gt; 'test_output1',
  'access arguments' =&gt; array('access content'),
  'type' =&gt; MENU_NORMAL_ITEM,
  'menu_name' =&gt; 'main-menu'
);


If you don't want the link to be added to a menu automatically at all, change MENU_NORMAL_ITEM to MENU_CALLBACK.

Remember to clear the caches when you make any change to hook_menu(), otherwise the changes won't be picked up.