WooChimp integrates WooCommerce store with MailChimp. MailChimp is an email marketing service provider. You can read more about it on their website.
When WooChimp is active, customers can be automatically added to any MailChimp mailing list on checkout. It's also possible to display an opt-in checkbox so customers can express their consent to be added to the list. This plugin comes with a standard WordPress widget that can be added to any sidebar on the webste. Widget displays a configurable newsletter signup form. This plugin also includes a shortcode that can be placed anywhere on the website (pages, posts, product description) to show a newsletter signup form.
WooChimp fully supports MailChimp's Ecommerce 360 functionality. If enabled, order data will be send to MailChimp and associated with subscribers. This allows advanced segmentation when creating email campaigns and autoresponders. Ecommerce 360 integration also allows full campaign-to-order tracking.
You can easily enable or disable any functonality that was described above from the administrator zone. Please refer to other sections of this documentation for more information.