beginner
Glossary & milestone quiz
One-screen recap, then ten questions. Pass with ≥7/10 to call yourself fluent in the foundations.
The whole track in one picture
Acronym cheat sheet
The tech world loves three-letter labels. Here are the ones you've met (and a few you'll meet next), each tied to its meaning so the letters stop being random.
| Acronym | Full form | How to remember |
|---|---|---|
| AI | Artificial Intelligence | Machines doing things that needed human intelligence. |
| ML | Machine Learning | Programs that learn from examples, not from rules. |
| LLM | Large Language Model | Large (huge) + Language (text) + Model (a learned program). |
| BPE | Byte-Pair Encoding | Common pairs of bytes (characters) get bundled into single tokens. |
| API | Application Programming Interface | The "front desk" one Application uses to ask another for something. |
| JSON | JavaScript Object Notation | Text with curly braces. Universal data format on the web. |
| TTFT | Time To First Token | The pause before the very First Token appears. |
| TPS | Tokens Per Second | How fast text streams once it's started. |
| RAG | Retrieval-Augmented Generation | Retrieve the right passage → Augment the prompt with it → Generate the answer. |
| CoT | Chain-of-Thought | Intermediate thinking steps before the final answer. "Think step by step." |
| RLHF | Reinforcement Learning from Human Feedback | RL (rewarding good behaviour) + HF (rewards come from humans rating responses). |
| MCP | Model Context Protocol | A protocol for giving any Model the right Context from any source. "USB-C for AI tools." |
| PII | Personally Identifiable Information | Any info that identifies a person — name, email, ID. |
| OCR | Optical Character Recognition | Optically reading characters (text) inside images. |
| GPU | Graphics Processing Unit | The chip type that powers AI training and inference. |
(Hover any acronym anywhere in the lessons to see its full form and memory hook.)
Plain-English glossary
| Term | If you only remember one thing… |
|---|---|
| LLM | A very, very good autocomplete. |
| Token | The chunks of text the model bills by. ~0.75 words per token in English. |
| Context window | The chef's counter. Everything in this conversation has to fit on it. |
| System prompt | The manager's brief — your rules and persona, set by the developer. |
| User / Assistant | The customer's question / what the assistant said earlier. |
| Temperature | Dice heat. 0 = always favourite. Higher = more variety. |
| Top-p | Roll the dice only among the top X% of probability mass. |
| Hallucination | Confident-sounding text that's plain wrong. |
| TTFT | The pause before the model starts speaking. The thing users feel. |
| Streaming | Speaking while still thinking — same total time, much better UX. |
| Prompt caching | The translator memorising the briefing instead of re-reading it. |
| Model routing | Cheap translator for easy questions, senior interpreter for hard ones. |
| RAG (medium track) | Giving the model the actual document instead of asking from memory. |
| Embedding (medium track) | A vector that captures meaning — used for semantic search. |
| Tool calling (medium track) | The model asks your code to run a function; reads the result; replies. |
| Agent (medium track) | An LLM in a while loop that can call tools. |
| Fine-tuning (advanced) | Continued training to specialise a model. |
Cheat sheet: what to reach for
A user asks a question →
├── Generic knowledge → just call the LLM (low temperature, good system prompt)
├── Needs your data → RAG (medium track)
├── Needs an action → tool calling (medium track)
├── Needs many steps → agent loop (medium track)
└── Custom voice or rare task → fine-tuning (advanced track)
Milestone quiz (10 questions)
Check your understanding
- 1. Roughly how many tokens are in 1,500 words of English prose?
- 2. Which roles can the developer set in a chat request?
- 3. You set temperature=0 and run the same prompt twice. Will the outputs match?
- 4. Stuffing 199k tokens into a 200k context window — what's the most likely problem?
- 5. Output tokens are typically priced about how much higher than input tokens?
- 6. Your model returns a citation to 'Smith v. Jones, 412 F.3d 891 (4th Cir. 2009)'. Best next step?
- 7. Which of these is NOT a real way to reduce hallucinations?
- 8. Which is most likely a single token in a modern BPE tokenizer?
- 9. What's the strongest combination for a chatbot that should never invent facts?
- 10. You move from a frontier model to a mid-tier model — CSAT drops 2 points but cost drops 80%. The right framing?
What's next
You're ready for the Medium track, where you'll learn how production LLM apps are actually built: embeddings, RAG, prompt engineering, tool calling, agents, evals, and caching. Things start to feel less like magic and more like systems.