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answer: direct
beat: system-design
source: 1 article · updated: August 11, 2026
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How does tokenization, stemming, and lowercasing affect the index?

Ingestion splits text into tokens, normalizes them to lowercase, and stems them to root forms (e.g., 'testing' → 'test'). This deduplicates terms across documents—'tests' and 'testing' both map to 'test'—reducing index size and improving recall so searches find more relevant results.

Answered in

The Inverted Index

A sorted dictionary mapping terms to document IDs. Transform search from O(corpus size) to O(1) lookup, enabling full-text search at scale.

Crashtech Editorial August 11, 2026 System Design

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