What are Large Language Models?
Understand the core concepts, capabilities, and limitations of Large Language Models (LLMs) and their role in modern AI.
What are Large Language Models? is a free LangChain / RAG / Vector DBs lesson on CoddyKit — lesson 1 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the LangChain / RAG / Vector DBs learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
What are Large Language Models?
Large Language Models (LLMs) power tools like ChatGPT. They are AI systems built to understand, generate, and process human language at the frontier of today’s AI.
The 'Large' in LLMs
The "large" in LLM means two things: billions or trillions of learned parameters, trained on enormous text datasets. That scale is what captures complex language patterns.
How LLMs Learn and Work
At heart, an LLM is a statistical model that predicts the next token in a sequence — like a wildly advanced autocomplete building sentences word by word.
Core Capability: Text Generation
The headline skill of LLMs is generating human-like text: stories, emails, summaries, code snippets, and natural conversation — making them powerful for creative and practical work.
Beyond Generation: Other Capabilities
Beyond writing, LLMs summarize long text, translate between languages, answer questions, and complete passages — versatile assistants for nearly any language task.
LLMs Don't 'Understand'
Key reality check: LLMs do not truly "understand". They are statistical engines that reproduce patterns from training data — no consciousness, emotions, or beliefs.
Limitation 1: Hallucinations
A major limit is hallucination: the model confidently states things that sound plausible but are flat wrong, inventing details when it lacks real information.
Limitation 2: Knowledge Cutoff
Another limit is the knowledge cutoff. An LLM only knows data up to its last training date — ask about recent events and you get stale or wrong answers.
Limitation 3: Bias in Responses
Because LLMs learn from human text, they absorb its biases too — so outputs can reflect societal bias. Mitigating it is an active area of research.
Test Your LLM Knowledge
Which of the following is a core limitation of Large Language Models (LLMs)?
LLMs: Powerful but Imperfect
LLMs are powerful but imperfect: brilliant at language, yet just statistical models prone to hallucinations, knowledge cutoffs, and bias. Knowing the limits is how you use them well.
Frequently asked questions
Is the “What are Large Language Models?” lesson free?
Yes — the full text of “What are Large Language Models?” is free to read here on the web, and the LangChain / RAG / Vector DBs course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the LangChain / RAG / Vector DBs course, upgrade to CoddyKit PRO.
What will I learn in “What are Large Language Models?”?
Understand the core concepts, capabilities, and limitations of Large Language Models (LLMs) and their role in modern AI. You practise LangChain / RAG / Vector DBs with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start LangChain / RAG / Vector DBs?
No prior experience is required. LangChain / RAG / Vector DBs on CoddyKit is structured for beginners through advanced learners; this is — lesson 1 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “What are Large Language Models?” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this LangChain / RAG / Vector DBs lesson?
Yes. Every LangChain / RAG / Vector DBs lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.
All lessons in this course
- What are Large Language Models?
- The Need for Retrieval Augmented Generation
- Core Components of a RAG System
- Embeddings and Vector Databases