A flow, like in workflow, is a group that combines several commands and executes them step by step.
Under the "Flows" tab you will an overview of your flows and here you can create new ones, rename, and reorder them.

Create a flow

Create a flow by clicking on the plus icon on the top right.

Run a flow

To run a flow you can just click on the play icon on the left and the flow will run once.
You can build a collection of powerful helpers (e.g. random opacity for selection) and trigger them from the overview.

Reorder flows

Change the order of flows just by drag and drop. Grab a flow and drag it to where you want it to be. New flows will always be added to the top of the list.

Edit the contents of a flow

Click on the chevron on the right to open a flow to customize it.