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answer: direct
beat: ai-learning
source: 1 article · updated: September 1, 2026
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What's the difference between fine-tuning and prompt engineering, and when do I use each?

Prompt engineering shapes model behavior through the input text — zero cost, instant iteration, works within a single API call. Fine-tuning updates the model's actual weights on a narrower dataset — it costs compute and data, but bakes behavior in permanently. Reach for prompting first; fine-tune only when prompting hits a ceiling you've actually measured.

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20 AI Concepts Every Developer Should Actually Understand

A layered glossary of the 20 AI concepts developers keep running into — grouped by dependency, not alphabetized, so each term builds on the one before it.

Crashtech Editorial September 1, 2026 Learning & Thinking with AI

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