Fact-checking sites are web sites that are attempt to counter misinformation and disinformation by fact checking internet memes, political speches and other sources of possibly unreliable information. Of course fact-checking sites can themselves have slips in reasoning, biases, and may struggle with complex science or technology.
Links:
bbc.co.uk: BBC Verify- reuters.com: Reuters Fact Check: Examining social media narratives and misinformation
- fullfact.org: Full Fact – UK independent fact check site