What type of auction allows bidders to anonymously bid on items?

A silent auction allows bidders to anonymously submit bids on items without revealing their identities to other participants. In this type of auction, bids are typically written down on sheets of paper placed next to the items or submitted electronically, ensuring confidentiality while participants engage in the bidding process. This format encourages more participants to bid without the pressure of competing openly in front of others, fostering a less intimidating atmosphere.

In contrast, open and live auctions involve participants openly bidding against each other, where their identities and bid amounts are visible to all. Sealed bid auctions also differ, as they involve bidders submitting their bids in sealed envelopes, but the key characteristic of anonymity is tied to silent auctions where continuing to monitor or change bids throughout the event is not possible. Thus, silent auctions uniquely provide the level of anonymity characterized in the question.