JavaScript this refers to window instead of object inside function

Question

I get confused on a JavaScript this reference situation.

I am working on a code that I declare function inside an object method. (The reason is to tidy

Answer 1

this has nothing to do with scope. It is determined by context.

greeting() calls the function with no context, so this is the default object (window in a browser).

Answer 2

The this, references is not related to scope, it depends on the calling context.

As per the MDN doc,

In general, the object bound to this in the current scope is determined by how the current function was called

Answer 3

Try person.nickname, this refers to the var greeting in your case