Scope

Introduction to scope

The concept of a variable’s “scope” is important in any programming language. The scope of a variable or function refers to the parts of the program where they can be accessed. Most languages have some form of lexical scope, which means the scope of a variable is based on where it appears in the code. Often placing a variable inside a block will restrict its scope to that block. A few languages, such as Perl and other Lisp-style languages, use dynamic scope, which means the scope of a variable can change while the program is running.

Global scope covers the entire the program. Any variable or function that can be accessed anywhere ...