Create Thumbnail For All Items Thumbnails are are reduced-size versions of your item pictures. This link allows you to create thumbnails for multiple items that already have a main image or have been imported.  The reason you would use this is to have smaller images for customers to see when they are browsing through products, and a larger image which they could view on the item page.

Create Thumbnail Options Choose the categories of products by checking the box next to the category you would like to create thumbnails for.  Next, click the  'Create Thumbnails'  button.