Advertising technology has built a massive technical infrastructure. The technology and motivations of advertising undergird the economy of the internet. News sites are no exception. The information we seek about our world is underpinned with, and shaped by, advertising and its needs. Journalists need to know more about these technologies, how they work, and how they influence the practice, distribution, and perception of journalism. Advertising technology may threaten the reputation and economic viability of news publishers in various ways. Ad tech promotes a specific type of audience engagement, and its incentive structures have been shown to alter how news gets produced, potentially undermining readers’ trust in publishers to provide objective coverage. Ad tech’s push of user data through opaque systems, and in some cases deposit malware onto readers’ devices, threatens reader privacy and safety and can further damage publishers’ reputations. The slow load times and distracting...