A quick summary. Google's replacing third-party cookies with browser-based tools. They say their goal is to increase user privacy and personalization. What are third-party cookies?
A third-party cookie's a cookie that's downloaded to your computer by your browser from a website OTHER than the one you're visiting. For example, you visit www.example.com and you receive a cookie from analytics.google.com.
a bit more about cookies:
Cookies are tiny bits of data stored on your computer. They are designed to store information on your computer for later use. Some examples include your shopping cart items in an eCommerce website (such as Shopify), information for analytics (like if you're a new or returning user), or login information (so when you return your preferences are saved). While this is all well and good, cookies also have some serious drawbacks if you're concerned with privacy.
As mentioned above, cookies provide and track data. And the tracking extends far beyond your current browsing session. Advertisers and marketers keep track of as much of your browsing history as possible, and use this to create mini-profiles and campaigns targetting you. Here's a common scenario I'm sure you've expereinced: you browse look up some information on a car, or visit a site to read some reviews about boots. Next thing you know, you begin seeing advertisements for everything you've recently browsed in popular social media channels like YouTube, Instagram and Facebook.
Does this mean in-browser advertising and targeted advertisements are gone? No. Instead, Google intends to gather your data directly through its browser Chrome (rather than through a cookie). Any leftover cookies will be handled differently, for example, their data will be sent only over HTTPS (instead of HTTP), amongst some other changes.
There's a bit of speculation and uncertainty on how exactly cookies will be handled, and the entire roadmap isn't out. So, in order to avoid speculation, I'll stop the article here and provide an update when more concrete information is available.