Deep Dive into LLMs like ChatGPT

211 minutesAdvancedChatGPT & LLMs

Andrej Karpathy. This is the clearest end-to-end explanation on YouTube of what an LLM actually is — pretraining, tokenization, SFT, RLHF, reasoning RL, tool use, hallucinations — at the level of detail an engineer needs to reason about model trade-offs. Watch it once and the "GPT-class vs. open-weights vs. reasoning model" decisions in the article stop feeling like brand choices and start feeling like training-recipe choices.

AI Expert note

Model names, pricing and capabilities change quickly. Use this for the decision pattern, then verify current model behavior before adopting it.

What you should get from this

Understand the modern LLM stack well enough to reason about tokens, training, tools and failures.

Watch next

Continue through the same learning path with the next curated companion videos.

Related videos

Take it further

Hand-picked external courses that go deeper on this topic.

See all courses for ChatGPT & LLMs