In computer science, a local variable is a variable that is given local scope. Such a variable is accessible only from the function or block in which it is declared. Local variables are contrasted with [[global alpha beta segato it. In most languages, these local parameters are treated the same as other local variables within the subroutine. In contrast, call by reference and call by name semantics allow the parameters to act as aliases of the values passed as arguments, allowing the subroutine to modify variables outside its own scope.
Some advocate that all variables should be of local scope to avoid issues with side-effects.
Static local variables
A special type of local variable, called a static local, is available in many mainstream languages, including C/C++, Visual Basic and VB.NET, which allows a value to be retained from one call of the function to another. In this case, recursive calls to the function also have access to the variable. In all of the above languages, variables are declared as such with a special storage class keyword (e.g., static).
Static locals in global functions can be thought of as global variables, because their value remains in memory for the life of the program. The only difference is that they are only accessible through one function. Static locals can also be declared in class-level functions in object-oriented languages.
Stricter and more formal object-oriented languages such as Java and C#, do not allow local variables to be declared static to a function. Instead, "static" variables in these languages are scoped to the class.
Note: This is distinct from other usages of the static keyword, which has several different meanings in various other languages.
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