There are 2 ways:
- Context related advertise - you are searching for “chairs” and will get some ads that matches this search. It’s also better to see chair ads right now, when you are looking for it instead of the next week, when you already bought it.
- Special channels where you can get information to products. This can be a YouTube Channel, a news paper that focus for example on tech devises and software or any other topic. And I’m fine with it since I expect to see some form of ad there … that’s normally the reason I visit such pages.
Both forms don’t need any feedback to give interests related advertise. I mean, Purism could sell me a product (L5) while I never heard about company and their pocket PC before.