# Using Processor node
Processor node can be used for building subflows and to implement looping functionality such as a simple for loop or a do-while loop. Processor node is also the only node in Kumologica which can be used for switching the default asynchronous nature of the flow to a synchronous or a sequential mode.
Implementing subflow in Kumologica using processor node
In this video we will be creating a simple main flow and a subflow which will be invoked from the main flow.
Implementing for loop in Kumologica using processor node
In this video we will be demonstrating how to do a simple for-loop using increment operation in processor node.
Implementing do-while loop in Kumologica using processor node
In this video we will be demonstrating the steps for implementing do-while loop using watch operation in processor node.