Smoking used to be everywhere, the way Facebook, TikTok, Snap, YouTube and Instagram are now. Society decided to break the habit, but it took a long time.

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Our reporter Cecilia Kang explains Meta’s settlement of a lawsuit claiming that the company’s social media platforms had harmed teenage users.

The social networking giant projected it could spend $10 billion annually on Anthropic’s tools, illustrating the friend-foe relationships underlying the A.I. race.

Meta, the social media giant, agreed to change the way children interact with its apps. That could be trouble if its competitors don’t abide by the same rules.

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