Day 16: Cosine Similarity and Semantic Search Basics

[PriyeshDave]

Lesson ready for review

Day: 16
Title: Day 16: Cosine Similarity and Semantic Search Basics
Phase: Phase 2 — Word Representations & Embeddings
Generated at: 2026-09-10T13:11:17.587154+00:00

Review checklist

• Technically accurate -- no confident-sounding but wrong explanations
• Jargon defined before first use
• Code (if present) is correct and matches what the text claims
• Recap of the previous day reads naturally (if present)
• "Coming up next" teaser is accurate to tomorrow's actual topic
• Matches the series' teaching voice (patient, not senior-engineer-only)

Merging this PR triggers publish.yml, which publishes to dev.to as part
of Zero to Agentic series. Edit the file directly in this PR
before merging if changes are needed.