[quote name='yahoosale14']what does fulfilled by amazon mean? its a 3rd party seller and fulfilled by amazon...[/QUOTE]
It means that a third-party seller has their items stored in an Amazon warehouse, and when you order it, Amazon physically gets the item and ships it to you.
So you're buying from the third-party seller, technically, and receiving the item from Amazon, as it's stored in their warehouse. So Amazon acts as a middleman pretty much.
Also, items from third-party sellers, stored in Amazon's warehouse, are eligible for Amazon services like FSSS, and Amazon Prime.