A while back, Google said that it was on board with the idea that cookies--the little pieces of software code that websites use to do all sorts of things like keeping you logged in, and letting an advertiser know when you've clicked on its ad and then made a purchase--were bad. At least, the third-party kind--the ones that track your activity across the internet. Those types of cookies would be blocked in Chrome by 2023.
Except, because Google--like every advertising platform--uses cookies to know what types of ads to show you, getting rid of them was complicated. Actually, it wasn't really that complicated for Google, which doesn't even need third-party cookies to know what you're interested in, since it literally runs the website where billions of people just tell it what they're looking for.
Google's real problem is that it can't just shut off third-party cookies entirely since that would be very bad for its competition and might look like it was leveraging the fact that not only does it control the world's largest advertising platform, but also its most popular web browser, Chrome. Considering the attention that regulators and lawmakers are paying to big tech companies, that was a non-starter.
So, Google said it would introduce an alternative known as Federated Learning of Cohorts or FLoC. The short version is that Chrome would track your browsing history and use it to identify you as a part of a cohort of other users with similar interests. Advertisers would then target ads to the "I like to buy expensive ski outfits" cohort, or the "I just turned 50 and have two kids about to enter college and want to re-finance my mortgage" cohort.
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