The AI terms worth knowing next

Five definitions for what happens inside a chat when memory runs out, an answer needs a source, or the model reaches for a tool.

Context window

How much text, files, and tool output a model can hold at once. Past that limit, earlier parts of the conversation fall out of view.

System prompt

Instructions loaded before you type. They set the role, tone, and boundaries, including what powers a custom assistant.

Grounding

Connecting a reply to a document, link, or record you trust, instead of letting the model guess from general training.

Hallucination

A confident answer that is wrong or made up. The model is predicting plausible wording, not checking the facts.

Tool use

When the model calls another system to search, look something up, or take an action, then folds that result into the reply.