Drop shipping is a retail fulfillment method where a store doesn't keep the products it sells in stock. Instead, when a store sells a product, it purchases the item from a third party and has it shipped directly to the customer. As a result, the merchant never sees or handles the product.
The biggest difference between drop shipping and the standard retail model is that the selling merchant doesn't stock or own inventory. Instead, the merchant purchases inventory as needed from a third party – usually a wholesaler or manufacturer – to fulfill orders. (Source - https://www.shopify.com/guides/dropshipping/understanding-dropshipping)
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