Set Values

Much like the Run Script workflow activity, Set Values simply allows you to set one or more fields on the record against which the workflow is running, to specific values. This is often used to set the State field, modify the actual start/end dates, and so on:

Note that, as with most Set value fields, you can dot-walk in this workflow activity to set values on related records! For example, you could set the parent.state field, if the record your workflow is running against is expected to have a parent, and you'd like to change the parent record's state based on something happening in the workflow.