The Conversions node displays all the conversion functions currently loaded. To change or add new conversion functions modify the formula file and load it. Conversion functions are special functions that get mapped to a telemetry point. In the Explorer view below you can see the conversion function EU which is defined for several telemetry points with potentially different algorithms/implementations. This allows to map one conversion function name to several mappings depending on telemetry point.
The right hand pane shows the data items the conversion function is defined for. Multiple data items can share the same conversion function name. The function body is listed as well as the formula file the conversion function was loaded from.