In this chapter a port is used to input data. It focuses on reading those data and making decisions based upon the data. Some basic switch configurations are provided which is used to stop and start the binary counting of the program. To implement the switch function, one component (switch), two icons (Input and Decision) and a new variable are added. It provides detailed information on working of the program. It also provides alternative ways to program a function. Use of Component Macros and Flowchart Macros are also described in the chapter.