Global variables

A global variable is one that is defined in the main program of a program or the main part of a unit. Globals declared in a program cannot be accessed from a unit, but globals in a unit can be accessed from a main program or a unit that accesses that unit.

 var
   i:integer;

 begin
 end.

i is a global variable.

External variable

External variable is a global variable has been declared in unit interface section.

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• Var
• Local_variables