Reference

AI glossary: the terms that carry weight

Short answerA short list of the AI terms that carry the most weight in governance and cost decisions, each defined in plain English and linked to the page that goes deeper.

These are the terms that do the most work across this library, defined in the same plain English the pages use. Where a page goes deeper, the term links to it.

A few pairs get confused often enough to be worth reading side by side: open weights and open source, a policy and an enforcement point, training and inference.

Agent
An AI system that takes actions on someone's behalf. It acts; it does not hand a recommendation to a person. More
Attention
The technique a transformer uses to weigh how much each part of an input bears on every other part. More
Attribution
Being able to prove, afterwards, who asked what and what the system did. More
Control point
Where an enforcement point actually sits in a deployment: the single place requests are routed through, so one rule covers every application. More
Deepfake
Synthetic audio, image, or video made to pass as a real recording of a real person. More
Developer liability
Responsibility resting on whoever designed and trained a system, by analogy to product liability. More
Enforcement point
The place in a system where a rule is actually checked, while something is happening and before it takes effect. More
Fine-tune
Adjusting an already-trained model on additional data to specialize it, without training it from scratch.
Generative AI
Systems that produce new content (text, images, code, audio) from patterns learned in training. More
Guardrail
A rule that catches a harmful AI request or response and stops it before a person sees it. More
Hyperscale
Data-center capacity at the largest tier: the facilities that frontier model training and high-volume inference require. More
Inference
Using a trained model to answer something. The ongoing cost of running AI. More
Observability
Being able to see who is using which AI, how much, and whether anything is going wrong, while it happens. More
Open source
Code, and often training data and license, published. Broader than open weights, and rarer in AI. More
Open weights
A model whose trained numbers are published, so anyone can run or adapt it. Not the same as open source. More
Operator liability
Responsibility resting on the organization that deployed a system, whoever built it. More
Parameter
Another word for a weight: one of the numbers that determine how an input becomes an output. More
Policy
A written rule. It becomes a control only when something enforces it automatically. More
Predictive AI
Systems that score or classify things that already exist. They do not produce new content. More
Provenance
The traceable origin of something: a model's training data, or a file's chain of custody. More
Runtime
While the system is actually running and serving requests, as opposed to when it was built or reviewed. More
Token
A small piece of text, roughly part of a word. AI usage is metered and billed in tokens.
Training
The one-time process of finding a model's weights from data. More
Transformer
The model architecture behind current language models. It reads a whole sequence at once, where earlier designs went word by word. More
Watermarking
A signal embedded in generated content so it can later be identified as synthetic. Probabilistic, and removable. More
Weight
One of the numbers inside a model that determines how an input becomes an output. More

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