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Glossary

AI words, in plain language.

40 terms explained in one or two sentences, linked to the guide that goes deeper.

AgentUse
An AI system that acts rather than just answers: it plans steps, uses tools (browser, files, apps) and checks results until the task is done. Learn more →
AI ActRules
EU Regulation 2024/1689 on artificial intelligence. It classifies systems by risk level and sets different duties for those who build and those who use them. Learn more →
AI literacyRules
The duty (AI Act Art. 4) to take measures so staff using AI understand how it works, its limits and risks. Since Regulation 2026/1744 a "sufficient level" no longer has to be guaranteed, but the duty still applies to everyone. Learn more →
APITechnical
The interface through which a program uses an AI model. You pay per use, by tokens read and written, rather than by subscription.
BenchmarkBasics
A standard test to measure a model (maths, code, reasoning). Useful for comparison, but it does not tell you how it will do on YOUR task. Learn more →
Chain of thoughtTechnical
"Thinking out loud": the model writes intermediate steps before answering. Reasoning models do it automatically, often hidden. Learn more →
Context windowBasics
How much text the model can "see" at once: the conversation, uploaded documents, instructions. Top models now reach about 1 million tokens. Learn more →
Deep researchUse
A mode where the AI browses dozens of sources autonomously for several minutes and produces a cited report. Learn more →
DeepfakeRules
Generated or manipulated image, audio or video that looks authentic. The AI Act requires disclosure; explicit sexual deepfakes are banned since 2026.
DeployerRules
In AI Act terms, whoever uses an AI system in a professional activity (a company, a firm). Different duties from the "provider" who builds it. Learn more →
DiffusionTechnical
The technique behind most image and video generators: the model starts from random noise and cleans it step by step into an image matching the description. Learn more →
EmbeddingTechnical
A list of numbers representing the meaning of a word or text. Similar texts have nearby embeddings: that is how "semantic" search works. Learn more →
Fine-tuningTechnical
Further training a ready model on your own examples to specialise it. Today good context or a Skill is often enough.
Frontier modelBasics
The most capable models available at a given time. As of October 2026: Claude Opus 5.5, GPT-6 Astra and Sol, Gemini 4 Argon, Muse Wonder.
GPUTechnical
The graphics processor used to train and run models: it does thousands of multiplications in parallel. Why NVIDIA is worth trillions.
HallucinationBasics
When a model produces false information stated confidently: a non-existent ruling, an invented number, a quote never said. Learn more →
HarnessTechnical
The scaffolding around a model: the program that gives it tools, memory and a work loop. The same model performs much better in a good harness. Learn more →
InferenceTechnical
Using an already-trained model to generate answers. What you pay for when you use an API or subscription.
Intelligence IndexBasics
Artificial Analysis's composite score combining several independent benchmarks. As of October 2026 the top is 58 (Claude Opus 5.5). Learn more →
LLMBasics
Large Language Model: a neural network trained on huge amounts of text to predict the next word. Learn more →
MCPUse
Model Context Protocol: an open standard to connect an AI assistant to external tools and data (Drive, calendar, ERP) without custom integrations. Learn more →
Mixture of Experts (MoE)Technical
A model split into many "experts", only some active for each word. Labels like "35B A3B" mean 35 billion parameters in total, 3 active at a time: lots of knowledge, small-model speed. Learn more →
MultimodalBasics
A model that understands (or produces) several content types: text, images, audio, video, PDF.
Open weightsBasics
Models whose weights can be downloaded: you can run them on your own servers without sending data to third parties. E.g. GLM-5.3, Kimi K3, DeepSeek V4, MiMo. Learn more →
ParametersTechnical
The numbers tuned during training: the model's statistical memory. Frontier models have hundreds of billions to trillions. Learn more →
PhishingRules
Messages imitating banks, suppliers or colleagues to make you click, pay or reveal credentials. With AI they are error-free: the signal is the request, not the wording. Learn more →
Pre-trainingTechnical
The first training phase: the model reads a vast share of the web and books, learning to predict the next token. Costs hundreds of millions. Learn more →
PromptUse
The instruction you give the model. A good prompt states role, goal, context, constraints and output format. Learn more →
Prompt injectionRules
An attack where instructions hidden in a page, email or document hijack the AI reading them. The main risk for agents. Learn more →
QuantisationTechnical
Reducing the precision of a model's numbers (e.g. to 4 bits) so it fits in less memory and runs faster, with a small quality loss. It's what lets open models run on an ordinary computer. Learn more →
RAGTechnical
Retrieval-Augmented Generation: before answering, the system retrieves relevant passages from your documents into the context. This site's chatbot works this way. Learn more →
Reasoning modelBasics
A model that thinks before answering, generating intermediate steps. More effort = better answers on hard problems, but more time and cost. Learn more →
RLHFTechnical
Reinforcement Learning from Human Feedback: the phase where the model learns from human preferences to be helpful, clear and safe. Learn more →
SkillUse
A bundle of instructions and files (procedures, templates, scripts) the assistant loads only when needed. It teaches it "how you work". Learn more →
TemperatureTechnical
A setting controlling randomness when picking the next word: low = predictable, high = more varied and creative. Learn more →
TokenBasics
The chunk of text a model works with: a short word, part of a word, a symbol. In English 100 words ≈ 130 tokens. Billing is per token. Learn more →
TransformerTechnical
The neural network architecture introduced by Google in 2017 ("Attention Is All You Need") behind every modern LLM. Learn more →
Vibe codingUse
Building software by describing what you want and letting AI write the code. Great for prototypes; production needs review. Learn more →
Voice cloningRules
Creating a synthetic copy of a voice from a few minutes (or seconds) of recording. Useful for dubbing and content, but it requires the person's consent and is used in scams. Learn more →
WatermarkRules
A (often invisible) mark identifying content as AI-generated. The AI Act requires it from 2 December 2026.