Data/ Control Flows, Information Flows
Graphically, there is no difference between data and control flows; solid lines are used for both.
Note: From external data sources or to external data sinks, draw data/control flows explicitly with flow-labels positioned in the external activities (“Pin-Labels”). There should only be one label at the source/sink for each signal.
Internal communication between function blocks is visualized by Information Flows. Thus there are no multiple flows internally between activities. The exception is when you have a flow with a fork (see the Internal and External Flow Lines figure.