There are two types of Actions: Simple and Advance. The difference is that when a simple action is created all information for its functioning is already known. For example, to turn on a dimmer to full brightness, setDimmer channel is to be activates and 255 value is to be sent there. The value is known beforehand. Advanced action is created on the basis of incomplete information about the action. In case with the dimmer, the brightness is to be set at any value from 0 to 255, but it is not clear what value is to be sent and when it has to be sent.