ps_image table...Please explain

[MrBaseball34]

Can anyone explain what the position and cover values are in the ps_image table?
I am trying to modify our import process to correctly work with 1.3.1 tables and this
is stumping me.

Table: ps_image
 id_image -------------+
 id_product -------+   |
 position          |   |
 cover             |   | Table: ps_image_lang
                   |   | 
                   |   + id_image
                   |     id_lang -----+
                   |     legend       |
   +---------------+                  | Table: ps_lang
   |  Table ps_product                |
   |                                  + id_lang
   + id_product                         name
     id_supplier                        active
     id_manufacturer                    iso_code
     id_tax                   
     id_category_default                   

[rocky]

The position value is used to determine what order the images are displayed on the product page. For example, the first image has position 1, the second position 2, etc. The cover value is used to choose which image is displayed on the product listing pages and in modules that link to the product. The cover image has a value of 1 and all other images on the product have a value of 0.