Hi,
I am a bit surprised that no one answered:
Global variable = A variable that effects the entire world (as opposed to local variable)..... is not limitted to a specific area / country / continent.
Automatic variable = A variable that is an automatic result of something else. One has no control of it, as something happend that veriable is an automatic result.
Static variable = A variable that doesn't (or very slightly) change with time. It is static in nature.
Best regards,