# Process Variables

Most CSS tools support several types of process variables (PVs). When simply using a PV name like

       some_pv_name

this will refer to a default PV type which can be configured in the PV preferences.

To select a specific PV type, use the PV name format

       type://some_pv_name

Consult the syntax of each data source for details.

## Preferences

The default PV type can be selected via the menu CSS/Preferences/Applications/Configuration/Process Variables.