In WordPress 3.7, there is new Auto Update feature which automatically updates WordPress to newest version when a Stable version is released, but sometimes you might have done some editing to WordPress core files or for any other feature, then you can disable Auto Update in WordPress.
Personally I think this feature is good and helpful for most of the people, but if you are a developer or a WordPress user for business needs then you might need to disable it
If for any reason you want disable Auto update in WordPress then add the below code in
define( 'AUTOMATIC_UPDATER_DISABLED', true );
After adding the code save the file, then all the auto updates for WordPress will be disabled, if you require a more Detailed Guide for Disabling follow this Topic on WP codex.