Evaluate Sources and Credibility

The internet hands you billions of pages, videos, and posts in a single search. Some are written by experts who cite their evidence; others are guesses, opinions, or outright lies dressed up to look real. Evaluating sources is the skill that decides whether your projects, your beliefs, and your decisions are built on facts or on noise.

The CRAAP Test

Librarians and journalists use a five-question checklist to judge any source. If a page fails even one of these tests, look for a stronger one before you cite it.

1. Currency — When was it written or last updated? Stale information can be flat wrong.
2. Relevance — Does it actually answer your question, or only brush past the topic?
3. Authority — Who wrote it? What are their credentials? Is the publisher reputable?
4. Accuracy — Are the claims backed by evidence, links, and citations you can check?
5. Purpose — Why was it published — to inform, to teach, to sell, or to persuade?

Primary, Secondary, and Tertiary Sources

• Primary — original evidence: a scientist's data, a witness account, an interview transcript, a photograph from the event.
• Secondary — analysis of primary evidence: a news article, a textbook chapter, a peer-reviewed paper that reviews experiments.
• Tertiary — summaries of summaries: encyclopedias, study-guide sites, AI overview boxes. Useful starting points, but cite the primary or secondary source.

Red Flags to Walk Away From

• No author or vague author — a generic Staff writer byline or no name at all means no accountability.
• No date or last updated years ago — facts and statistics go stale, fast.
• Strong emotional language — loaded words like shocking, destroyed, or they-do-not-want-you-to-know signal persuasion, not information.
• No citations or links — claims without sources are just opinions.
• Suspicious URL — domains like .news.click or look-alike spellings of real sites are common scam patterns.