A fact is a statement that can be verified. Statements of opinion are not facts.
Fact checkers often focus on claims that can be verified with hard data from authoritative sources. Many of the claims that fact checkers examine are numerical claims, since these are easily verified.
Fact checking is, in a word - Research. Fact checking is researching the truth of a statement in order to verify its accuracy.
Professional fact checkers are employed by various news and media outlets.
In an election, each candidate is aiming to get the most votes. Many times, candidates say things that they think will help them get the most votes. However, this doesn't mean that the candidates are actually being truthful. Consider this:
You need to do your research in order to know how much of what each candidate says is actually true.
In order to be an informed voter, and an informed citizen, you need to do your research and think critically about what you find in this research.
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