GLOSSARY Opt-in / Opt-out A B C D E F G H I J K L M N O P Q R S T U V W X Y Z User consent or refusal to receive ads or share data. Back to index Related concepts O&O (Owned and Operated)Omni-channelOn-Device ProcessingOnline advertisingOpen AuctionOpen ExchangeOpenRTBOpenRTB (Open Real-Time Bidding)