AI Glossary

24 AI terms explained in plain English. No jargon, no PhD required. Click any term for the full definition with real-world analogies.

A

AI Agent

An AI that can actually do things for you, not just talk about them.

AI Concepts

API

The behind-the-scenes way apps plug AI into their own product.

Core Concepts

B

Benchmark

A common exam for AI models so we can compare them fairly.

AI Concepts

C

Chain-of-Thought

Asking the model to show its working instead of jumping straight to an answer.

Techniques & Methods

Context Window

The model’s short-term memory size for one conversation turn.

Core Concepts

E

Embedding

A way to turn meaning into numbers so machines can compare ideas.

Technical Terms

F

Fine-tuning

Teaching a strong general model to become better at your specific job.

Technical Terms

Function Calling

How a model asks software to actually do something, like search, fetch, or send.

Technical Terms

G

GPT

The label used for OpenAI’s main language model series.

Models & Products

H

Hallucination

When the AI makes something up and says it as if it were true.

AI Concepts

I

Inference

Actually using the model after training is finished.

Technical Terms

L

Large Language Model (LLM)

The technology behind tools like ChatGPT, Claude, and Gemini.

Core Concepts

M

Multimodal

An AI that can read, look, listen, and sometimes speak or generate media.

AI Concepts

O

Open Source / Open Weights

AI you can download, run yourself, and often modify.

AI Concepts

Output Tokens

The words the AI writes back to you.

Core Concepts

P

Prompt

The message you send to the AI.

Core Concepts

Prompt Engineering

Learning how to ask AI the right way so it gives better results.

Techniques & Methods

R

RAG

Letting the AI look things up before it answers.

Techniques & Methods

Reasoning Model

A model built to think longer and more carefully on difficult questions.

AI Concepts

RLHF

Training the model based on which answers people preferred.

Technical Terms

S

System Prompt

The hidden instructions that tell the AI how it should behave.

Core Concepts

T

Temperature

A creativity dial for the model’s responses.

Parameters & Settings

Token

The small pieces of text AI counts, reads, and bills you for.

Core Concepts

Transformer

The core invention that made today’s powerful AI models possible.

Technical Terms