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Neural network

Also: neural networks

In plain words

A model made of linked layers of maths. Training adjusts its numbers so it can learn patterns from data.

Billions of tiny dials

A model is a huge set of dials, each holding a number. Training turns the dials a little at a time, over millions of examples, until the model’s guesses are good. After training the dials are locked: using the model does not change them, and showing it your document does not teach it anything permanent.

The fuller definition

A neural network is a computational arrangement of connected units and learned numerical parameters. Layers transform inputs into representations used to produce outputs.

Go deeper

A small neural-network schematic
Input valuesLearned transformationsOutputs

Lines represent computational connections with learned values. This tiny diagram illustrates a neural network; a transformer or mixture-of-experts model has additional structures not shown here.

A concrete example

A small network combines input values, applies transformations, and outputs a classification score.

The distinction that matters

The name is inspired by biology; an artificial network is not a literal digital brain.

Related terms

Where it is taught

What actually happens when you ask AI a question?

Source and further reading

Google · Machine Learning Glossary

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