Featured Image
The featured post image is the main image for your product. It is the image which will be displayed within your product loops (IE on product categories, up sells, related products etc) and the initial focus of the image gallery on your product details page.
Product Galleries
Product galleries simply display all images attached to a product, with the Featured Image being the primary image. You can create a product gallery using the same method as adding a featured image, rather using the Product Gallery meta box instead.
Editing Images
Images in the product gallery can be re-ordered easily via drag and drop. Simply re-order your images by moving them around.
To remove an image from the product gallery, hover over the image and click on the red “x”.
WooTheme’s Guide: https://docs.woothemes.com/document/adding-product-images-and-galleries/
