How Search Engines Rank Results (Simplified with Real Signals)
Search feels magical until you break it down. At its core, ranking is about matching intent with the best available content.
The Three Big Signals
1. Relevance
Does the content match the query? This is often measured with TF-IDF or BM25.
2. Authority
Is the source trusted? Links act as endorsements.
3. Freshness
For time-sensitive queries, newer content ranks higher.
Ranking Is a Weighted Score
A simplified score:
$$score = 0.5 \times relevance + 0.3 \times authority + 0.2 \times freshness$$
The weights vary by query type.
Practical Example
For “latest iPhone release”:
- Freshness weight increases.
- Old authoritative pages drop.
For “TCP congestion control”:
- Authority weight dominates.
- Freshness is less important.
Final Thought
Search is not one algorithm. It is a balancing act. The best systems adapt signals to the query intent.
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