I still remember the Tuesday I accidentally swiped right on my high-school lab partner—on Facebook, not Tinder. My phone buzzed, and suddenly “Chemistry 2.0” was more than a class; it was a potential date. Here’s the thing: none of it would’ve happened if I hadn’t first unlocked Facebook Dating,...

Facebook has made its first foray into the online secondhand market with its new Marketplace feature, which is currently rolling out to users. It’s a local version of Craigslist where users can list their unwanted items for sale at a fixed price in their city. The new feature also...