Parameters
Parameters are the internal numbers a model adjusts during training — the "dials" of a neural network. Large language models have billions or even trillions of them. More parameters can mean more capability, but data quality and training methods matter just as much.
In one line, for a 12-year-old
Parameters are the billions of little settings inside an AI that get tuned while it learns.
An example
A "7B" model has about seven billion parameters — small enough to run on a good laptop.
Why it matters to people
Parameter counts are often used as marketing. A smaller model that runs on your own device can be the more private and cheaper choice.