Also known as: general-purpose AI model
In plain English
A foundation model is a big, general-purpose AI that many products are built on, like the foundation of a house. One foundation model can power a chatbot, a writing assistant and a coding tool.
In practice
Most AI products you buy are built on a few foundation models from providers such as OpenAI, Anthropic, Google and Meta. That creates a dependency: when the underlying model changes, the product's behaviour can change too, so ask vendors which model they use.
Under the hood
The term was coined at Stanford in 2021 for models pre-trained at scale with self-supervised objectives and then adapted by fine-tuning, prompting or retrieval. Regulation uses related language; the EU AI Act, for example, sets rules for "general-purpose AI models".
Example
"All three vendors on our shortlist run on the same foundation model."