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Large language model (LLM)

Also: large language models, LLMs

In plain words

A program trained on enormous amounts of text so it can read and write language. ChatGPT and Claude are built on large language models.

What the model actually does: guess the next piece

“The judge entered the ___”

courtroom72%
room15%
building6%
fray3%

It picks a word, adds it to the sentence, and guesses again, thousands of times a second. Everything it writes, from a poem to a legal memo, is built this way. That is why it can be fluent and wrong at the same time: it is predicting what sounds right, not checking what is true.

The fuller definition

A large language model is a neural network trained on large collections of language data to model patterns in token sequences. It can generate and transform text; some model families also process other modalities.

Go deeper

How it fits together
  1. Text

    The supplied passage

  2. Tokens

    Numerical input sequence

  3. Output

    Generated continuation

A simplified relationship, not a screenshot or a complete design.

A concrete example

A model completes a draft sentence or summarizes a supplied passage, using its training and current context.

The distinction that matters

Language fluency does not establish that a statement is true or supported by the record.

Related terms

Where it is taught

What actually happens when you ask AI a question?

Source and further reading

Google · Machine Learning Glossary

The definition and example are written for this library. The link gives background, official documentation or legal authority as labelled. Legal scope depends on the jurisdiction and current text; product features depend on release and settings.

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