What is AI?

Artificial Intelligence (AI) is software that can do tasks that used to need a person — like writing, translating, or answering questions. But AI does not "think" or "understand" the way a human does.

The best way to picture today's AI is as a very good pattern-matcher. It has seen an enormous amount of text and learned which words tend to follow other words. When you ask it something, it predicts the most likely next words, one at a time, until it has a full answer.

> Think of your phone keyboard. When you type "Good", it suggests "morning". AI does the same thing — just far, far better, and for whole sentences and paragraphs.

What is an LLM?

The kind of AI you will use in this course is called a Large Language Model, or LLM. "Large" means it learned from a huge amount of writing. "Language Model" means its job is to work with words.

An LLM is not a robot with feelings, and it is not connected to a brain. It is a program that is very good at guessing what text should come next.

Keep this simple idea in mind: AI predicts likely words. It is a tool, and you are the one guiding it.