A wholesaler is a person/company that carries a line of products and sells them in bulk (a lot of the same products)to a retailer store, market, etc. who, in turn, sells the product to the public. i.e., when you buy a shirt the wholesaler has ordered X number of shirts from the manufacturer and, in turn, has orders for X, Y, Z number of shirts from different stores. By the time you buy the shirt it has been marked up (euro increases on base price) by the the wholesaler and the store where you purchased it.

Make sense?