Variable Scope: Global or Local

Variable Scope refers to the location in code where variables can be used in a program.

Global Variables Variables defined outside any functions are visible and usable throughout the program - in any code below where they have been declared.

Local Variables: If a variable is defined as part of a function definition, then the variable belongs to that function. The variable has local-scope. The variable is only visible within that function, when that function is being executed, when the function has completed execution, the local-variables no longer exist.

Local Variables Hide Global Variables within a function Within a function's definition, if a local variable has the same name as a global variable, the global variable is hidden by the local variable, this is global variable hiding. Local variables have higher status than global variables within a function.