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In the image below, Books, Stationery and Games & Toys are families.
The rank determines the ranking of this family in the list. On the previous image, Books was ranked 1 while Games & Toys was ranked 3.
The image
If your Goods catalog is big, you can also divide each Family in sub-families in order to perform sub-groupings of Products. Then you will be able to link a product directly to the sub-family.
Example : you could have a family Clothes, that you will divide in sub-families Trousers, Sweater, T-shirts, socks...
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