I have read the link : hook_menu
Snippet from the page
"access callback": A function returning TRUE if the user has access rights to this menu item, and FALSE if not. It can also be a boolean constant instead of a function, and you can also use numeric values (will be cast to boolean). Defaults to user_access() unless a value is inherited from the parent menu item; only MENU_DEFAULT_LOCAL_TASK items can inherit access callbacks. To use the user_access() default callback, you must specify the permission to check as 'access arguments' (see below).
"access arguments": An array of arguments to pass to the access callback function, with path component substitution as described above. If the access callback is inherited (see above), the access arguments will be inherited with it, unless overridden in the child menu item.
But Still unclear about what access arguments are actually used for ? Are the access arguments the permissions ?