I am new to ubuntu, and tried to use OpenFOAM Installation worked OK; after that I copy-pasted the very first example, worked also OK. but I cannot understand how. There are funny commands like:
mkdir -p $FOAM_RUN
This creates the folder structure
cp -r $FOAM_TUTORIALS $FOAM_RUN
This copies the tutorials in the above mentioned folder
What does the sign
These commands work when copy-pasted, but I want understanding them and being able to use them later on.