content moderation Written by Sarah T. Roberts Contributor to SAGE Publications's The SAGE International Encyclopedia of Mass Media and Society (2020) whose work appears in Britannica as part of a joint publishing agreement with SAGE. Sarah T. Roberts Fact-checked by Britannica Editors Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree.... Britannica Editors Last updated May 4, 2026 •History Every day, billions of people worldwide sign onto the world’s social media platforms, consuming and producing massive amounts of digital media material for dissemination to friends, their communities, and the world. These media and the resulting activity related to their consumption—users’ status updates, likes and favorites, comments, posts, photo and video uploads, and so on—constitute what is known in the social media industry as user-generated content (UGC). The system of review and sometimes removal of...

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