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Model, service, and feature
What this means: Three distinct layers: a model generates answers, a service makes the model available under its own terms and settings, and a feature is one function of the service, such as search or file reading. The same model can be used in multiple services with different terms.
Mental modelStable concept
Sources and review
Reviewed September 10, 2026
Also known as
model, service and feature
Explained in guides
- Open AI models — a low-pressure first tryWhat an open language model means, how to try one at your own pace without an account, and when a regular online service is the easier choice.
- Model, service and feature: three different layersDistinguish a language model, the service that uses it and an application feature, and learn where to check privacy information and terms of use.
- What is Llama? — a model family for beginnersLlama is Meta’s language model family. Learn how to check whether an app uses it and what open weights and its licence actually mean for you.
- Choose an AI assistant by testing the same taskTry one request in two assistants, judge their answers against the same criteria, and choose a tool you can use with confidence.
- Check what an AI service does with the information you typeBefore giving a service your notes or other material, use its own guidance and your account settings to answer three questions, then record the answers with the date.