A sealed-bid auction is a type of auction where all bidders submit their bids privately and simultaneously. Each bidder writes down their offer without knowing what others have bid. Once all bids are submitted, the auctioneer opens them, and the highest bidder wins the item. This format encourages bidders to submit their best offer without the influence of competing bids. In a sealed-bid auction, bidders must carefully consider their strategy, as they cannot adjust their bids after seeing others. This method is often used for selling government contracts or real estate, where transparency and fairness are essential.