I’m Michael. I was a principal engineer at Facebook from 2009 to 2017, where I was the top code contributor of all time and also conducted hundreds of interviews. I recently co-founded Formation.dev, an engineering fellowship that trains and refers engineers directly into big tech. Ask me Anything!

Hi! A lot of people have noticed these kinds of things too, even my family. So I haven't been at Facebook now for a few years, but as far as I was aware was absolutely no listening to conversations to show you ads and there also isn't a single reason you would see those ads. These are some of the possibilities: * You happen to be really similar to others in very scary ways that are almost impossible to believe. Some of these ad providers build profiles based on your demographics and have gotten scary accurate in making predictions about you. For example, if there's a trend forming of people similar to you on paper starting to go to a specific fast food restaurant, you might start getting ads targeted to you for that restaurant. And then coincidentally a friend also similar to you who just went to this trendy restaurant might be talking to you about it around the same time. * Someone in your house or sharing internet searching for the thing you are talking about without realizing it. Say you are at the dining room table talking with your sibling about something and a parent in another room overhears and searches for it, you might get ads targeted toward your IP address not realizing that other person even overheard you.