Oracle has tried to give as many interfaces/ codes as possible, to the functional consultants, where they can key in codes and tweak the flow of the system and processes as per their demand. However usage of codes is not possible in each and every process of the application. There was a need of sub-programs that can be written by the Functional guys, so that it will be referred by the application to decide on the process. Those are like decision making sub-programs that ultimately return values, with which the application can decide the flow. Those sub-programs are called Fast Formula.