Global Variable F3
Global variables in MetaTrader 5:
MetaQuotes:
I read through the above 3 web sites. They only explain what global varibles mean but don't explain or don't provide any example how the global varibles work. For example Global variables in MetaTrader 5:

what are the gvar0 1.2, gvar1 1.7, gvar2 0.3? Where will those gvars be applied to? How do they affect the MT5?
How to use the Global Variable F3 in MT5?