It’s hard to tell the difference between what’s an ad and what’s not these days on Pinterest. A search for “women’s hiking pants” on the platform yields hundreds of vivid, pleasant images of the outdoors—very few of which don’t lead to a checkout page on a retailer’s site. You’ll see a mix of promoted Pins from popular athletic gear retailers like Fabletics and Athleta, as well as “Shoppable Pins” and “Shop the Look” pins from retailers. The platform classifies the latter two as “non-ads,” even though clicking on either will direct users to a link for purchase. Shoppable Pins display the current price of the item, and clicking on them takes you directly to the retailer’s site, where users can purchase the item itself. Brands upload Shoppable Pins to Pinterest, and then users share them organically. Similarly, with “Shop the Look” pins, retailers and influencers can tag any products for sale in photos. Read more at Quartz.