Technology & ComputingSpiralIntermediate12 chapters
How large language models work, without the hype
HippoCampus· starter course
Explain how large language models actually work — tokens, neural networks, training, transformers, why they make things up — clearly and without hype in either direction.
What you'll learn
12 chapters
1What an LLM Is and Is Not
- Form a grounded overview of large language models as statistical text-prediction systems.
- Separate common myths from the core engineering reality of how LLMs operate.
- Identify the main stages in an LLM's lifecycle that the rest of the course will revisit.
2From Text to Tokens
- Explain why raw text must be converted into tokens before a model can process it.
- Describe tokenization as a practical compromise between character-level and word-level representation.
- Connect tokenization choices to model behavior, cost, and context length.
3Representing Language with Numbers
- Describe how tokens are turned into numeric representations a neural network can use.
- Build an overview understanding of embeddings as learned representations rather than hand-coded meanings.
- Recognize that positional information must also be represented for sequences.
4Neural Networks as Pattern Learners
- Explain the basic idea of a neural network as layered function approximation.
- Relate weights, activations, and training adjustments to pattern learning from data.
- Place LLMs within the broader family of machine learning systems.
5The Transformer Breakthrough
- Identify the transformer as the architecture behind modern LLMs.
- Explain attention in broad terms as selective weighting of context.
- Understand why transformers scaled better for language modeling than earlier sequence models.
6How Training Actually Works
- Describe pretraining as repeated next-token prediction over very large text datasets.
- Explain the roles of loss, optimization, and backpropagation at an overview level.
- Connect scale in data, parameters, and compute to model capability.
7From Base Models to Helpful Assistants
- Explain how a raw pretrained model is adapted into a more usable assistant.
- Survey fine-tuning, instruction tuning, and feedback-driven alignment at a high level.
- Recognize that post-training changes behavior without changing the basic prediction mechanism.
8How Inference Produces Responses
- Describe what happens when a trained model receives a prompt and generates text.
- Explain token-by-token generation and the role of sampling choices.
- Connect prompting and decoding settings to differences in output style and reliability.
9Why Models Make Things Up
- Give a non-mystical explanation for hallucinations and confident errors.
- Distinguish fluent language generation from guaranteed factual accuracy.
- Relate failure modes to training objectives, missing knowledge, and prompt context.
10What LLMs Are Good At, and How We Evaluate Them
- Survey the main capability areas where LLMs often perform well and where they struggle.
- Introduce evaluation as comparing model behavior against tasks, benchmarks, and human judgment.
- Encourage nuanced assessment rather than blanket claims of intelligence or uselessness.
11LLMs in Real Systems
- Place the model inside practical applications rather than treating it as a stand-alone magic box.
- Identify common system components such as retrieval, tools, guardrails, and user interfaces.
- Understand that many useful products combine LLMs with external software and data.
12Limits, Costs, and Societal Tradeoffs
- Summarize the main technical, economic, and social constraints around LLMs.
- Recognize issues such as bias, privacy, copyright concerns, energy use, and misuse without reducing the subject to fear or hype.
- Develop a balanced view of where LLMs fit in society and work.