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🔬Beginner8 lessons · 3 free

How LLMs Actually Work

You cannot build reliable AI products without understanding why LLMs behave the way they do. Why does temperature matter? Why does prompt length affect cost? Why do models confidently make things up? Why does the same prompt produce different results tomorrow? This course builds the foundational mental model — not the mathematics, but the intuition — that separates builders who fight their models from builders who work with them.

No prerequisites — pairs well with Generative AI for Builders
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$29one-time · lifetime access

What you'll learn

How transformers work — attention, parameters, and next-token prediction explained plainly
Tokenisation — what models actually see, context window costs, and the lost-in-middle problem
Temperature, top-P, and top-K — why outputs vary and how to control randomness
How models are trained — pretraining, RLHF, and Constitutional AI (how Claude was built)
The 2026 model landscape — Claude vs GPT-4o vs Gemini vs Llama and when to choose each
System prompts and roles — the three message roles and how the model uses them
Why hallucinations happen — the mechanism, and how to mitigate them in production
Model selection framework — quality, latency, cost, and the routing pattern

Course outline

Full course — $29 one-time

04

How Training Works

Pretraining, RLHF, fine-tuning, and why the same base model can behave very differently

9 min
05

The Major Models Compared

Claude vs GPT-4o vs Gemini vs Llama — beyond the benchmarks to real-world builder trade-offs

9 min
06

System Prompts and Roles

How the conversation is actually structured under the hood — and how to use it effectively

8 min
07

Hallucinations and Why They Happen

The mechanism behind confabulation — and the architectural patterns that reliably reduce it

8 min
08

Choosing the Right Model

A practical framework for matching model capabilities to task requirements — cost, speed, quality

7 min

Get the full course

8 lessons — from tokens and attention to model selection, hallucination mitigation, and the model routing pattern.

8 lessons✓ Beginner-friendly, technically accurate✓ Certificate
$29one-time

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