its where you set an exact number of credits to "purchase" it instantly if you dont wanna wait for the bidding to be done. for example if you dont wanna wait 7 days you could set a gin price of 2000 credits and first one to accept it gets the item
Something else that you should know about GIN is that first of all it costs a fee in credits when posted, and secondly, Listia also takes a commission after it's been won. Also you can't do GIN once there is a bid on the auction.