JavaScript function scope and Lexical scope

Original Sticker Address: http://pierrespring.com/2010/05/11/function-scope-and-lexical-scoping/

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Wikipedia defines Scope as follows:

Tipically, scope is used to define the extent of information hiding--that are, the visibility or accessibility of

Variables from diefferent parts of the program.

Scopes are used to define the depth of information hiding-the accessibility of variables in a section elsewhere in the program.

In JavaScript we have Function scope and Lexical scope.

Function Scope means that any variable which are defined within a function is visible within that entire function .

This was quite different form Block scope, in which a variable scopes is limited by the block a variable are declared in.

Function Scope means that any variable defined inside a function is visible to the entire function .

JavaScript function scope and Lexical scope