They are replacing the way ad and content revenue is being distributed through their tokens. Users who use their Brave browser (which is wickedly fast, btw, I'm using it right now) can opt to have all ads blocked - but if you elect to have Brave's ads on, then we get 'paid' in BAT for keeping our attention. And we can also use the BAT to 'donate' to sites we frequent - some other stuff coming down the pipe. Basically it's eliminating Google from leeching the majority of money from advertisers and content creators.