Facebook, Twitter, Instagram and YouTube routinely remove posts deemed to violate standards on violence, sexual content, privacy, harassment, impersonation, self-harm and other concerns. Most of those actions happen automatically, through decisions by artificial intelligence. (Especially during the pandemic, companies became more reliant on machine learning to police their platforms, often resulting in over-enforcement, or content coming down that may not have violated rules.) More rarely, the platforms ban users (such as radio provocateur Alex Jones, removed from Facebook, YouTube and Apple for engaging in hateful speech) or entire topics, such as QAnon, the fringe conspiracy theory that imagines a globalized pedophilia cabal infiltrating the U.S. Democratic Party. Also, Facebook Inc. and Alphabet Inc.’s Google partner with third-party fact-checkers to vet posts and news items that may be suspect. Twitter Inc. labels posts that contain misleading or disputed claims.