91 concepts to understand artificial intelligence
Eight chapters, eight entries to read
Artificial intelligence answers our questions, completes our sentences, creates images and organizes our access to information. It is everywhere, but what do we really know about how it works? What is a model? How does a machine learn? What are a token, a vector, fine-tuning or a hallucination?
This living lexicon offers a clear, rigorous and accessible introduction, free of fantasies and easy fears. Organized in thematic chapters, it reads like a story: from the most fundamental to the most applied, from inside the models to their effects on the world.
The eight chapters
1. What Artificial Intelligence Is
Before getting into technical detail, let’s start with the basics. What is artificial intelligence? (15 concepts)
Imitation Game · Artificial Intelligence · Generative Artificial Intelligence · Algorithm · Model · Phases (of a Model) · Training · Inference · Fine-Tuning · Foundation Model · Agent · Alignment · Transparency · Explainability · Open Source
- Excerpt to read: Artificial Intelligence · page 22
2. What an AI System Contains: Neurons and Parameters
Inside every artificial intelligence lies a complex mathematical structure: neurons, weights, functions, layers, and so on. (16 concepts)
Perceptron · Neuron · Parameter · Weight · Bias (Parameter) · Activation Function · Layer · Neural Network · Backpropagation · Attention · Transformer · Language Model · Large Language Model · Reasoning Model · Diffusion Model · Multimodal
- Excerpt to read: Neuron · page 40
3. What (and How) AI Learns: Forms of Learning
An AI system is not programmed in the classic sense of the word: it learns. But what does learning mean for a machine? (11 concepts)
Learning · Machine Learning · Supervised Learning · Unsupervised Learning · Reinforcement Learning · Deep Learning · Dataset · Training Data · Personal Data · Pattern · Overfitting
- Excerpt to read: Machine Learning · page 58
4. What AI “Understands”: Language, Images, Sound
Artificial intelligence does more than process numbers: it handles language, analyzes images, recognizes voices. (9 concepts)
Natural Language Processing · Chatbot · Generative Pre-trained Transformer · Machine Translation · Speech Recognition · Text-to-Speech · Computer Vision · Facial Recognition · Image Generator
- Excerpt to read: Natural Language Processing · page 71
5. The Language of Models: Tokens and Computation
What does an AI system “see” when it reads a word, an image or a sentence? It does not understand the way a human does: it computes. (6 concepts)
Token · Context Window · Vector · Probability · SoftMax · Temperature
- Excerpt to read: Token · page 83
6. What AI Produces: Answers, Errors, Hallucinations
AI answers, predicts, generates. But it can also get things wrong, distort or invent. (12 concepts)
Input / Output · Prompt · Chain of Thought · Retrieval-Augmented Generation · Context Drift · Hallucination · Algorithmic Bias · Over-elaboration · Sycophancy · Black Box · Prompt Injection · Deepfake
- Excerpt to read: Hallucination · page 96
7. AI in Our Digital Lives: Filters, Engines, Interfaces
Artificial intelligence structures our everyday digital uses: it filters, ranks, recommends, moderates. (10 concepts)
Personalization · News Feed · Recommender System · Collaborative Filtering · Ranking · Content Moderation · Spam Detection · Filter Bubble · Latency · Vibe Coding
- Excerpt to read: Recommender System · page 107
8. Where Is Artificial Intelligence Going? Horizons, Risks, Questions
Artificial intelligence is advancing quickly, and with it come decisive questions. (12 concepts)
Computing Power · Agentic AI · Artificial General Intelligence · Consciousness (Sentience) · AI Scheming · AI Psychosis · Existential Risk · AI Ecological Impact · AI Race · Sovereign AI · AI Governance · Responsible AI
- Excerpt to read: Agentic AI · page 118
How to cite this book
Vial, S. (2026). A Living Lexicon of Artificial Intelligence. Stéphane Vial, publisher, Montréal.