Scope and Context: Together but not mixed

December 02, 2015— 3604 days ago, 0 views.

About Context

Context is related to objects. It refers to the object within which a function is executed.

When you use the new keyword in front of a function call, the context is the new Object.
When you execute a Function using .call or .apply, the context is the first argument.
If a Function is called as object property (like obj.fn) then is executed in the context of the Object.
If any of this rules don’t match with your case, the Function is executed in the global context.

Scope has to do with the the visibility of variables. In JavaScript, scope is achieved through the use of functions

Each function creates a scope, and the only way to create an scope is defining a Function.
The life cycle of an variable exists in the most external scope that the variable has been assigned.
Out of his scope, a variable is invisible.

Quotes from Kevin Chisholm blog.