Lesson 2 of 3Module 1 · 0% of course
LLMs & AI Engineering · How LLMs work

Preview: how LLMs work (tokens, attention, training)

A big-picture preview for the FDE path: an LLM is a next-token predictor trained on huge text, then tuned to be helpful. Python part 2 stays next in the main sequence.

35 min · 7 steps · videoJump to quiz ↓
[1hr Talk] Intro to Large Language Models Andrej Karpathy · 60 min
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Step 1 of 7 · 1. Text → tokens → numbers35 min read ·

1. Text → tokens → numbers

A model never sees letters. Text is split into tokens (common words or word pieces); each token becomes an id, then a vector (embedding). Roughly, 1 token ≈ ¾ of an English word.

"Trade T2 qty mismatch"
your text
→
Tokens
Trade | T | 2 | qty | mismatch
→
Embeddings
vectors
→
Transformer layers
attention + MLP
→
Next-token probabilities
'between' 31%, ':' 18% …
Next: 2. Attention
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