# Groups

> A group is a reusable sub-patch. Each instance has its own state.

Source: https://docs.tune.toys/concepts/groups/

A group packages part of a patch as a named definition you can place more than once.

## What it does

A group node refers to another definition in the same Toy. Each instance owns independent mutable state, so two instances of a delay group have separate echoes. Values set on the group node apply to that instance only. Groups can nest, within the limits of the format.

## Tips

- Expose only the controls you want as public parameters of the group.
- Frame membership is explicit: placing a group does not add its controls to a Frame automatically.

## See also

[Frames](https://docs.tune.toys/concepts/frames/), [Cables](https://docs.tune.toys/concepts/cables/).