AI Terms Explained in Plain English

What are the different types of AI?

There are a few ways to slice it:

• By capability: narrow AI does specific tasks, and it's the only kind that exists today, including ChatGPT. Artificial general intelligence (AGI) would match people across almost any task. It doesn't exist yet, and experts disagree about when, or whether, it will.
• The textbook four types: reactive machines, limited memory, theory of mind, and self-aware AI. Only the first two exist. Today's AI is "limited memory": it learns from data and uses context, but it doesn't understand minds or have awareness.
• By approach: rule-based systems follow instructions people wrote, machine learning learns patterns from data, deep learning uses large neural networks, and generative AI creates new text, images, audio, or video.

What is generative AI?

Generative AI is AI that creates new content, like text, images, audio, video, or code, in response to a prompt. It learns patterns from huge amounts of example data and uses them to produce something new rather than copying an existing answer. ChatGPT, Claude, and Gemini generate text and code; image and video tools generate pictures and clips from a description.

That's different from traditional AI, which mostly classifies or predicts: flagging spam, recommending a product, or forecasting demand. Generative AI produces. Many modern tools do both.

What does LLM mean?

LLM stands for large language model: an AI model trained on huge amounts of text to predict and generate language. The models behind ChatGPT, Claude, and Gemini are LLMs. "LLM vs AI" is really "one kind of AI vs the whole field": every LLM is AI, but most AI isn't an LLM.

What does AI-native mean?

AI-native describes something built around AI from the start rather than having it added later. An AI-native company designs its product and processes on the assumption that AI does much of the work. An AI-native product wouldn't make sense without AI. An AI-native worker reaches for AI tools as naturally as email.

The glossary

Artificial intelligence (AI)

Software that does things we'd normally say require intelligence, like understanding language, recognizing images, or making decisions.

Machine learning

AI that learns patterns from examples instead of following rules a person wrote.

Deep learning

Machine learning using large neural networks with many layers. It powers most modern AI.

Neural network

A system of connected mathematical units, loosely inspired by the brain, that learns by adjusting the strength of its connections.

Generative AI

AI that creates new content, like text, images, audio, video, or code.

Large language model (LLM)

A generative AI model trained on huge amounts of text to understand and produce language.

GPT

Short for "generative pre-trained transformer," the family of models behind ChatGPT. People sometimes use it loosely to mean any chatbot model.

Model

The trained AI itself: the file of learned patterns that turns input into output.

Training

Teaching a model by showing it huge amounts of data. It's slow and expensive, and done before you use it.

Inference

Using a trained model to get an answer. Every prompt you send is inference.

Prompt

The instructions or question you give an AI. Better prompts get better answers; try the free AI prompt builder.

Token

A chunk of text, often part of a word, that models read and write. Usage and prices are usually measured in tokens.

Context window

How much text a model can consider at once, including your prompt, documents, and the conversation so far.

Hallucination

When an AI states something false with confidence, like a fake citation or a wrong number.

RAG (retrieval-augmented generation)

Having an AI look up relevant documents first and answer from them, which cuts hallucinations and keeps answers current.

Fine-tuning

Further training an existing model on your own examples to change its style or specialize it.

Multimodal

AI that works with more than one kind of input or output, like text plus images or audio.

Chatbot

A program you talk to in conversation. Modern chatbots are usually built on LLMs.

AI agent

AI that takes a goal, decides the steps, and uses tools to carry them out. See what is an AI agent.

Agentic AI

AI systems that work toward goals over several steps with some independence.

Open-weight model

A model whose trained weights are published so anyone can run it on their own hardware.