–What is a bid request?–
–A bid request is a signal sent by your bidder to Ad Exchange asking for information on available inventory to bid on.–
–A bid request is a signal sent by Ad Exchange to your bidder describing publishers who have inventory available for bidding on.–
–A bid request is a signal sent by your bidder to Ad Exchange, containing bid information and an HTML snippet with a creative to compete in the auction.–
–A bid request is a signal sent by Ad Exchange to your bidder describing an impression being auctioned.–