Some communities on the social news site Reddit (known as "subreddits") are devoted to explicit, violent, or hateful material, and have been the topic of controversy. Controversial Reddit communities sometimes receive significant media coverage.
When Reddit was founded in 2005, there was only one shared space for all links, and subreddits did not exist. Subreddits were created later, but could only initially be created by Reddit administrators. In 2008, subreddit creation was opened to all users.
Reddit rose to infamy in October 2011, when a report by CNN showed that Reddit was harboring the r/jailbait community, which was devoted to sharing suggestive or revealing photos of underage girls. After commenters were seen asking for nude photos of underage girls, and under significant external scrutiny, Reddit shut down r/jailbait.
In 2012, the subreddit r/Creepshots received major backlash due to being a subreddit for sharing suggestive or revealing photos of women taken without their awareness or consent. Adrian Chen wrote a Gawker exposé of one of the subreddit's moderators and identified the person behind the account, starting discussion in the media about the ethics of anonymity and outing on the Internet.
In 2015, Reddit introduced a quarantine policy to make visiting certain subreddits more difficult. Visiting or joining a quarantined subreddit requires bypassing a warning prompt. In addition, quarantined subreddits do not appear in non-subscription based (aggregate) feeds such as r/all in order to prevent accidental viewing, do not generate revenue, and their user count is not visible. Since 2018, subreddits are allowed to appeal their quarantine.
Due to Reddit's decentralized moderation, user anonymity, and lack of fact-checking systems, the platform is highly prone to spreading misinformation and disinformation. It has been suggested that those who use Reddit should exercise caution in taking user-created unsourced content as fact.