The button node can be connected to any other parameter input. It does not pass any data to the connected parameter and will only affect when the node runs. When you press the play button, the button node will cause all downstream nodes to run (as if you had pressed the double-play button on the node the button is connected to). The input parameter to the button node can be published ⚡allowing the button to be used to trigger only a connected subset of nodes in your Runchat within the App View.