How ChatGPT Works (No Jargon)

You don't need to be a computer scientist to understand how ChatGPT works. In this lesson, we'll explain it in plain English using everyday analogies.

The Simple Explanation

Imagine ChatGPT as a student who has read millions of books, articles, websites, and conversations. This student doesn't memorize everything word-for-word, but learns patterns about how language works and how people communicate.

When you ask ChatGPT a question, it uses what it learned from all that reading to predict what words should come next - kind of like how your phone suggests the next word when you're texting.

The "Next Word" Game

Here's a fun way to understand it. If I say:

"The cat sat on the..."

What word comes to mind? Probably "mat" or "chair" or "floor" - words that commonly follow that phrase.

ChatGPT does something similar, but much more sophisticated. It considers:

• The words you've written
• The context of the conversation
• Patterns from everything it learned during training

Then it generates the most likely helpful response, one word at a time.

Training: How ChatGPT Learned

Before ChatGPT could help you, it went through a learning process called "training." Here's how it worked:

Step 1: Reading Everything

ChatGPT's creators fed it enormous amounts of text:

• Books and articles
• Websites and forums
• Conversations and dialogues
• Educational content

This happened before ChatGPT was released - the information has a "cutoff date" beyond which it doesn't have knowledge.

Step 2: Learning Patterns

From all this text, ChatGPT learned:

• How sentences are structured
• What questions typically get what answers
• How different topics relate to each other
• Various writing styles and tones

Step 3: Fine-Tuning

Human trainers then helped improve ChatGPT by:

• Rating its responses
• Teaching it to be more helpful and safe
• Correcting mistakes and bad behaviors

What's Happening When You Chat

When you send a message to ChatGPT, here's what happens in a fraction of a second:

1. Your message is received - ChatGPT reads what you wrote
2. Context is considered - It looks at your message plus any previous messages in the conversation
3. Response is generated - Based on patterns it learned, it predicts helpful text
4. Output is delivered - You see the response on your screen

When you try the prompt above, ChatGPT draws on what it learned about:

• Photosynthesis (from science content)
• Simple explanations (from educational content)
• How to write for children (from age-appropriate content)

What ChatGPT Doesn't Do

Understanding what ChatGPT can't do helps set realistic expectations:

It Doesn't Search the Internet

When you ask a question, ChatGPT doesn't go to Google. It answers from what it learned during training. This means:

• It doesn't know recent news (after its training cutoff)
• It can't check current stock prices or weather
• It doesn't access your personal files or emails

Note: ChatGPT Plus has a "Browse" feature that can search the web, but this is separate from its core knowledge.

It Doesn't Remember You

Each conversation starts fresh (unless you enable memory features). ChatGPT doesn't remember:

• Your previous conversations
• Personal details you shared before
• Your preferences from past chats

It Doesn't "Think" Like Humans

ChatGPT produces text that sounds thoughtful, but it's actually:

• Predicting likely words based on patterns
• Not reasoning through problems like humans do
• Not having opinions or feelings

The Temperature Setting Analogy

When ChatGPT generates responses, there's a behind-the-scenes setting that affects how creative or predictable it is. Think of it like a dial:

• Low setting (predictable): Gives safe, expected answers
• High setting (creative): Takes more chances, more varied responses

You don't control this directly, but it helps explain why ChatGPT might give different answers to the same question.

Why Does ChatGPT Sometimes Make Mistakes?

ChatGPT can confidently say things that are wrong. Here's why:

1. Pattern matching, not fact-checking - It predicts likely text, not verified truth
2. Training data had errors - Some sources it learned from had mistakes
3. No real-world knowledge - It can't verify information against reality

This is why you should always fact-check important information from ChatGPT.

A Helpful Mental Model

Think of ChatGPT as:

A very well-read writing assistant who can quickly draft text on almost any topic, but who might occasionally get facts wrong and needs you to review their work.

This mindset will help you:

• Use ChatGPT effectively for drafting and brainstorming
• Remember to verify important facts
• Understand that it's a tool, not an oracle

Try It: See Patterns in Action

Ask ChatGPT the same question in two different ways and notice how the responses differ:

Version 1:

Version 2:

The second prompt gets a more specific, useful response because you gave ChatGPT more context to work with.

Key Takeaways

• ChatGPT learned from reading millions of texts and now predicts helpful responses based on patterns
• It generates text one word at a time, choosing what's most likely to be helpful
• It doesn't search the internet or remember previous conversations (by default)
• It can make mistakes because it's pattern-matching, not fact-checking
• Think of it as a knowledgeable assistant whose work you should review

Now that you understand how ChatGPT works, let's get you set up with your own account in the next lesson!