What AI Actually Is
You've used ChatGPT or Gemini or Claude, but what actually happens when you hit enter?
The big idea: it's a function
At its core, an LLM — large language model — is a function, the same kind you met in high school algebra. f(x) = x + 2: pass in 1, get 3 — the same thing every time.
The internals of an LLM is astronomically larger than an algebraic function, but it’s still text in, text out. Pass in "The cat sat on the" and it returns the most likely next word: "mat." That's the whole trick — predict the next word — done by billions of numbers doing simple math, very fast. Do that well enough, at scale, and you get something that can write, summarize, and answer questions.
ChatGPT is not an LLM
ChatGPT is an app wrapped around an LLM. Before your message ever reaches the model, the app loads it up with extras — your conversation history, your account details, the date, tone instructions.
That's why the same question gets different answers on different days: the wrapper (plus a randomness dial called temperature) changes what actually hits the model. The model itself is just math.
Prove it yourself (5 min)
Open whatever chatbot you already use — ChatGPT, Claude, Gemini, doesn't matter.
- Prediction, live. Type: "Finish this sentence: the cat sat on the". You just watched next-word prediction happen in the open.
- The wrapper at work. Ask the same question in two brand-new chats — try "What should I make for dinner tonight?" Different answers. The model didn't change; the inputs and the dice did.
- No memory. Open one more brand-new chat and ask: "What did we just talk about?" Nothing. LLMs don't remember you — chat apps just quietly paste your history back in every time.
It isn't conscious, it isn't moody, and it doesn't know you.
Decode the buzzwords
Now headlines read differently. When someone says the AI "hallucinated" or is "learning," there's a plainer truth underneath. Keep the Buzzword Decoder handy — it's the hype-to-reality translation table for eight terms you'll hear constantly.
Review in video
LLMs don't remember you
Go deeper (optional homework)
- Stop Talking About AI Like It's Human — why the words we use muddy our understanding (4 min)
- LLMs Don't Remember You! — the full story behind experiment #3 (5 min)
- AI Isn't Magic: Explain It to Your Friends — the deep dive, good for sharing (members) (8 min)
Next up
Lesson 2: Your first real automation. You'll stop chatting with AI and start making it do work for you — something real running on your computer in 20 minutes. Want a head start? Try Build Your Own Baby Chatbot!, where you make a tiny app that shows next-word prediction from the inside.