The set of all global variables is known as the global environment or global state. The specific uses vary across different programming languages with the notions of scoping Variable shadowing in computer programming, variable shadowing occurs when a variable declared within a certain scope (decision block, method, or inner class) has the same name as a variable declared in an outer scope
At the level of identifiers (names, rather than variables), this is known as name masking.
The most common variable types in c++ are local variables inside a function or block, and temporary variables
[6] the common feature about automatic variables is that they have a lifetime that is limited to the scope of the variable. While the term can refer to global variables, it is primarily used in the context of nested and anonymous functions where some variables can be in neither the local nor the global scope. The dynamic loader calculates the address referred to by a global variable and stores the value in such global variable Pages with code and pages with global variables that do not contain pointers to code or global data remain shared between processes.
A global variable or static variable can be declared (or a symbol defined in assembly) with a keyword qualifier such as const, constexpr, constant, or final (when it is applied to primitive types), meaning that its value will be set at compile time and should not be changeable at runtime. A second use case would be multiple threads accumulating information into a global variable To avoid a race condition, every access to this global variable would have to be protected by a mutex. In computer programming, scope is an enclosing context where values and expressions are associated
The scope resolution operator helps to identify and specify the context to which an identifier refers, particularly by specifying a namespace or class
