“Fake news websites (also referred to as hoax news) deliberately publish hoaxes, propaganda, and disinformation — using social media to drive web traffic and amplify their effect." (Wikipedia) Fake news websites are not merely news organizations that are biased in their reporting, nor are they tabloid news or satirical news.
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While a news source may come from a reliable database, it is still important to critically evaluate the content. Peer-review and other forms of checks and balances make it more difficult for false information to get through, but these are not perfect systems.