Forks
In some cases there is a need to run multiple applications or graphs in parallel, this can be easily achieved by creating forks. To create a fork is not more complicated than building the main graph. Just connect the applications in the usual manner from the same source vertex to each individual vertex that you would like to fork out to.
Forks are denoted using the following icon 
on the edges, an edge without the icon is the main fork.
If there is a need to collect forks and/or control the behaviour before continuing in the graph you have to make sure that you use a barrier.