Prompt, token, context window

AI 101: The 2026 Foundation — lesson 4 of 20 (DEFINITION)

A prompt is your input. A token is a chunk of text (~¾ of a word) — models read and bill in tokens. The context window is the model’s working memory: how much it can consider at once, now often 200K+ tokens (a whole book).

Source: Anthropic Docs — Glossary

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