As of my last update in September 2021, Google AdX, also known as Google Ad Exchange, is an ad exchange platform developed by Google. It serves as a real-time marketplace where publishers can sell their advertising inventory to advertisers. AdX operates as a part of the larger Google Ad Manager ecosystem. Here's how it generally works

 1. Publishers: These are website owners or app developers who have ad space available on their digital properties. They want to monetize their content by displaying advertisements. 

 2. Advertisers: These are businesses or individuals who want to promote their products or services through online advertising. 

 3. Ad Exchange: Google AdX acts as an intermediary between publishers and advertisers. It allows publishers to put their available ad space up for auction, and advertisers can bid in real-time to display their ads in that space. 

 4. Real-Time Bidding (RTB): AdX operates on a real-time bidding system. When a user visits a website or app with available ad space, an ad request is sent to the exchange. Advertisers then bid on that ad space based on their targeting preferences, budget, and the value they place on that specific impression. 

 5. Ad Serving: The highest bidding ad from the advertiser wins the auction and gets displayed on the publisher's website or app to the user. Google AdX provides various targeting options, allowing advertisers to reach their desired audience effectively. It also provides publishers access to a wide range of advertisers, increasing the competition for their ad inventory and potentially leading to higher revenue. It's essential to note that the world of digital advertising is continuously evolving, and Google may have introduced new features or changes to AdX since my last update. Therefore, it's recommended to refer to the latest information from Google or other reliable sources for the most up-to-date details on Google AdX.